View source for Menstrual cup

{{Short description|Menstrual hygiene device, an elastomeric cup worn inside the vagina to catch menses}}
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[[File:Менструальный диск и менструальная чаша (cropped).jpg|alt=A menstrual disc and mentrual bell are held next to each other. The disc is larger in diameter and flatter. It has a similarly thick rim and thinner material in the basin.|thumb|214x214px|'''Left:''' blue bell-shaped thick-walled menstrual cup (also called a menstrual bell); '''right:''' pink bowl-shaped thin-walled cup (also called a menstrual disc or ring). Note crumpling of the ring-shaped cup.]]

A '''menstrual cup''' is a [[feminine hygiene|menstrual hygiene]] device which is inserted into the [[vagina]] during [[menstruation]]. Its purpose is to collect menstrual fluid (blood from the [[uterine lining]] mixed with other fluids). Menstrual cups are made of elastomers ([[silicone rubber]]s, [[latex]] rubbers, or [[thermoplastic rubber]]s).<ref>{{Cite news |date=2021-03-18 |title=Menstrual Cup Materials Explained: Silicone, Latex & Thermoplastic Elastomer (TPE) |url=https://meluna-usa.com/blogs/allaboutreusablemenstrualcare/menstrual-cup-materials-explained-silicone-latex-tpe |access-date=2024-03-17 |website=MeLuna USA |language=en |archive-date=17 March 2024 |archive-url=https://web.archive.org/web/20240317173058/https://meluna-usa.com/blogs/allaboutreusablemenstrualcare/menstrual-cup-materials-explained-silicone-latex-tpe |url-status=live }}</ref><ref>{{Cite web |date=2023-10-16 |title=Menstrual Cups Made from Thermoplastic Elastomer (TPE) |url=https://meluna-usa.com/blogs/allaboutreusablemenstrualcare/menstrual-cups-made-from-thermoplastic-elastomer-tpe |access-date=2024-03-17 |website=MeLuna USA |language=en |archive-date=17 March 2024 |archive-url=https://web.archive.org/web/20240317173058/https://meluna-usa.com/blogs/allaboutreusablemenstrualcare/menstrual-cups-made-from-thermoplastic-elastomer-tpe |url-status=live }}</ref> A properly fitting menstrual cup seals against the vaginal walls, so tilting and [[handstand|inverting]] the body will not cause it to leak.<ref name="PN-topQ"/> It is impermeable and collects menstrual fluid, unlike [[tampons]] and [[menstrual pad]]s, which absorb it.<ref name="stewart">Elizabeth Gunther Stewart, Paula Spencer: ''The V Book: A Doctor's Guide to Complete Vulvovaginal Health'', Bantam Books, 2002, Seiten 96 und 97, {{ISBN|0-553-38114-8}}.</ref><ref>Leslie Garrett, Peter Greenberg: ''The Virtuous Consumer: Your Essential Shopping Guide for a Better, Kinder and Healthier World'', New World Library, 2007, Seiten 17 bis 19, {{ISBN|1-930722-74-5}}.</ref>

Menstrual cups come in two types. The older type is bell-shaped, often with a stem, and has walls more than {{convert|2|mm|abbr=on}}  thick.<ref name=UNspec/> The second type has a springy rim, and attached to the rim, a bowl with thin, flexible walls. Bell-shaped cups sit over the [[cervix]], like [[cervical cap]]s,<ref name="invivoMRI"/> but they are generally larger than cervical caps{{refn|name=relative_size|refn=text=Cervical caps come in internal diameters of 22-31mm,<ref name="capVSdiaphragm">{{cite journal |last1=Gallo |first1=MF |last2=Grimes |first2=DA |last3=Schulz |first3=KF |title=Cervical cap versus diaphragm for contraception. |journal=The Cochrane Database of Systematic Reviews |date=2002 |volume=2002 |issue=4 |article-number=CD003551 |doi=10.1002/14651858.CD003551 |pmid=12519602|pmc=8719323 }}</ref> while bell-shaped cups come in sizes of ~31-53mm external diameter and as long as the wearer's cervix height permits.<ref name="PNsizechart"/>}} and cannot be worn during vaginal sex. Ring-shaped cups sit in the same position as a [[contraceptive diaphragm]]; they do not block the vagina and can be worn during vaginal sex.<ref name="thingstoknow">{{cite news |last1=Hendricks |first1=Sara |date=November 10, 2021 |title=10 things I learned from testing every menstrual cup on the market |url=https://reviewed.usatoday.com/health/features/using-menstrual-cup-things-to-know |work=USA Today |language=en}}</ref><ref name="discFAQ">{{cite web |last1=Ultimo |first1=Caitlin |title=All of the Menstrual Disc Questions You Have, Answered. |url=https://www.periodnirvana.com/all-of-the-menstrual-disc-questions-you-have-answered/ |website=Period Nirvana |date=28 December 2023 |access-date=14 March 2024 |archive-date=14 March 2024 |archive-url=https://web.archive.org/web/20240314191211/https://www.periodnirvana.com/all-of-the-menstrual-disc-questions-you-have-answered/ |url-status=live }}</ref> Menstrual cups are not meant to prevent pregnancy.

Every 4–12 hours (depending on capacity and the amount of flow), the cup is emptied (usually removed, rinsed, and reinserted). After each period, the cup requires cleaning.<ref>{{cite book |last1=Hillard |first1=Paula J. Adams |last2=Hillard |first2=Paula Adams |title=The 5-minute Obstetrics and Gynecology Consult |date=2008 |publisher=Lippincott Williams & Wilkins |isbn=978-0-7817-6942-6 |page=322 |url=https://books.google.com/books?id=fOoFIQOdIhkC&pg=PA322 |language=en}}</ref> One cup may be reusable for up to 10 years, making their long-term cost lower than that of disposable tampons or pads, though the initial cost is higher. As menstrual cups are reusable, they generate less [[Municipal solid waste|solid waste]] than tampons and pads, both from the products themselves and from their packaging.<ref name="Van2019" /> Bell-shaped cups have to fit fairly precisely; it is common for users to get a perfect fit from the second cup they buy, by judging the misfit of the first cup. Ring-shaped cups are one-size-fits-most, but some manufacturers sell multiple sizes.<ref name="disc/cup">{{cite web |last1=Rosas |first1=Kim |title=Menstrual Cup or Disc - Which to choose? |url=https://www.periodnirvana.com/menstrual-cup-or-menstrual-disc-which-to-choose/ |website=Period Nirvana |date=5 October 2020 |access-date=12 March 2024 |archive-date=12 March 2024 |archive-url=https://web.archive.org/web/20240312015039/https://www.periodnirvana.com/menstrual-cup-or-menstrual-disc-which-to-choose/ |url-status=live }}</ref>

Reported leakage for menstrual cups is similar or rarer than for tampons and pads.<ref name="Van2019" /> It is possible to [[urinate]],<ref name="top5">{{cite web |last1=Shastry |first1=Sharmada |title=5 Frequent Questions of Cup-Curious Folks! |url=https://www.sochgreen.com/5-frequent-questions-of-cup-curious-folks/ |publisher=SochGreen |access-date=19 March 2024 |date=12 July 2018 |archive-date=19 March 2024 |archive-url=https://web.archive.org/web/20240319182444/https://www.sochgreen.com/5-frequent-questions-of-cup-curious-folks/ |url-status=live }}</ref> [[defecate]], sleep, [[swimming|swim]],<ref name="PN-topQ">{{cite web |last1=Ultimo |first1=Caitlin |title=Top Menstrual Cup Questions, Answered |url=https://www.periodnirvana.com/top-menstrual-cup-questions-answered/ |website=Period Nirvana |access-date=19 March 2024 |date=16 November 2023 |archive-date=19 March 2024 |archive-url=https://web.archive.org/web/20240319182444/https://www.periodnirvana.com/top-menstrual-cup-questions-answered/ |url-status=live }}</ref> do [[gymnastics]],<ref name=rubysport/> run, ride [[bicycles]]<ref name=Lancet_review/> or [[riding animal]]s, weightlift, and do heavy exercise while wearing a menstrual cup.<ref name=rubysport>{{cite web |title=The Best Menstrual Cup for Sports Enthusiasts and Athletes |url=https://rubycup.com/blogs/articles/best-menstrual-cup-sports |website=Ruby Cup |date=14 January 2022 |language=en |access-date=19 March 2024 |archive-date=19 March 2024 |archive-url=https://web.archive.org/web/20240319182444/https://rubycup.com/blogs/articles/best-menstrual-cup-sports |url-status=live }}</ref> Incorrect placement or cup size can cause leakage.<ref name="Van2019" /> Most users initially find menstrual cups difficult, uncomfortable, and even painful to insert and remove. This generally gets better within 3–4 months of use; having friends who successfully use menstrual cups helps, but there is a shortage of research on factors that ease the learning curve. Menstrual cups are a safe alternative to other menstrual products; risk of [[toxic shock syndrome]] infection is similar or lower with menstrual cups than for pads or tampons.<ref name=Van2019>{{cite journal | vauthors = van Eijk AM, Zulaika G, Lenchner M, Mason L, Sivakami M, Nyothach E, Unger H, [[Kayla Laserson|Laserson K]], Phillips-Howard PA | title = Menstrual cup use, leakage, acceptability, safety, and availability: a systematic review and meta-analysis | journal = The Lancet. Public Health | volume = 4 | issue = 8 | pages = e376–e393 | date = August 2019 | pmid = 31324419 | pmc = 6669309 | doi = 10.1016/S2468-2667(19)30111-2 |doi-access=free}} [[File:CC-BY icon.svg|50px]] Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License] {{Webarchive|url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/ |date=16 October 2017 }}</ref>

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== Terminology ==
[[File:Gray1166.png|thumb|upright=2|Cross-sectional diagram showing the [[uterus]], cervix, fornix on either side of the cervix, vagina, and [[pubic symphysis|pubic bone]]. Ring-shaped cups lie in the upper portion of the vagina, with the inner edge in the posterior fornix and outer one held in behind the pubic bone, within the [[pelvic floor]].]]
The terminology used for menstrual cups is sometimes inconsistent. This article uses "menstrual cup" to mean all types, and for clarity, distinguishes the two main types as "bell-shaped" and "ring-shaped". <!--The thick-walled cups are bell-shaped, and they usually but not always have a rim somewhat thicker than the thick, springy body; they look like contraceptive [[cervical cap]]s. The thin-walled cups are usually more bowl-shaped (the bowl may have a deep dimple, for grip). They have a springy rim which is much thicker than the membrane of the baglike body; they look like [[contraceptive diaphragm]]s.

Some menstrual cups have solid, hollow, or ring-like protrusions called ''stems''; on thick-walled cups, they are attached at the point of the bell, and on thin-walled cups they are attached to the rim.-->

The thick-walled bell-shaped cups are the older type, and the term "menstrual cup" is sometimes used to refer only to bell-shaped cups. But in modern formal contexts, such as academic research<ref name=Lancet_review/> and regulations,<ref>see next paragraph</ref> "menstrual cup" usually refers to both types.

The US Food and Drug Administration holds that "A menstrual cup is a receptacle placed in the vagina to collect menstrual flow."<ref>{{cite web |title=CFR - Code of Federal Regulations Title 21 |url=https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm?fr=884.5400 |website=www.accessdata.fda.gov |access-date=14 March 2024 |archive-date=14 March 2024 |archive-url=https://web.archive.org/web/20240314191211/https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm?fr=884.5400 }}</ref> The EU legislated that "The product group 'reusable menstrual cups' shall comprise reusable flexible cups or barriers worn inside the body whose function is to retain and collect menstrual fluid, and which are made of silicone or other elastomers."<ref name="EUecolabel">{{cite journal |title=COMMISSION DECISION (EU) 2023/1809 of 14 September 2023 establishing the EU Ecolabel criteria for absorbent hygiene products and for reusable menstrual cups |journal=Official Journal of the European Union |date=22 September 2023}}</ref>

Ring-shaped cups are also called "'''menstrual discs'''" and sometimes "'''menstrual rings'''",<ref name="ring">{{cite web |last1=Hale |first1=Shelby |title=Menstrual Disc 101: How to Use One and Who They're For |date=21 July 2022 |url=https://www.miracare.com/blog/menstrual-disc/ |publisher=Mira |access-date=19 March 2024 |archive-date=19 March 2024 |archive-url=https://web.archive.org/web/20240319150557/https://www.miracare.com/blog/menstrual-disc/ |url-status=live }}</ref> to distinguish them from bell-shaped cups. Bell-shaped cups are sometimes called "'''menstrual bells'''".<ref name="bell">{{cite web |last1=Mathews |first1=David |title=Menstrual Cup: An Alternative To Tampons? - Fitt Feast |url=https://fittfeast.com/menstrual-cup/ |date=13 December 2022 |access-date=19 March 2024 |archive-date=19 March 2024 |archive-url=https://web.archive.org/web/20240319143559/https://fittfeast.com/menstrual-cup/ |url-status=live }}</ref>

Because bell-shaped cups are commonly depicted as being placed in the vaginal canal, well below the cervix, they are also called "'''vaginal cup'''s", with the ring-shaped cups called "'''cervical cup'''s". This may not clearly reflect their position in the body. [[MRI imaging]] suggests that, contrary to some manufacturer's depictions, the bell-shaped cups called "vaginal cups" are placed over the cervix, in a position similar to a [[cervical cap]] (not to be confused with a cervical ''cup'').<ref name="invivoMRI">{{cite journal |last1=Friberg |first1=M |last2=Woeller |first2=K |last3=Iberi |first3=V |last4=Mancheno |first4=PP |last5=Riedeman |first5=J |last6=Bohman |first6=L |last7=Davis |first7=CC |title=Development of in vitro methods to model the impact of vaginal lactobacilli on Staphylococcus aureus biofilm formation on menstrual cups as well as validation of recommended cleaning directions. |journal=Frontiers in Reproductive Health |date=2023 |volume=5 |article-number=1162746 |doi=10.3389/frph.2023.1162746 |doi-access=free |pmid=37671283 |pmc=10475951 }}</ref> Ring-shaped cups, called "cervical cups", also cover the cervix, but have one edge next to the cervix, and the other located further down the vagina, so that the cup is nearly parallel to the long axis of the vagina.<ref name="JWH2011"/>

In the 1800s, menstrual cups were called "''''catamenial sacks'''",<ref>{{patent|US|70865|Improvement in menstrual receiver}} A 1867 patent describes a sack fitting partly or wholly inside the vagina, suspended from a ring around the cervix, but with the ring held up by a U-shaped wire, which is fastened to the sack at one end and to a belt at the other. Quote:"I construct my menstrual receiver by forming a cup-shaped ring, ''a'', made of rubber, gum, gold, silver, or any suitable substance, which may be made round, or elliptical, or of any shape to fit the ''[[os uteri]]''. Around the lower orifice of ring is attached a sack or bag, ''b'', made of rubber or any suitable materials. The ring a rests-around the ''os uteri'', and the bag ''b'' rests entirely in the vagina, or may be made of such length as to rest parily outside and partly inside. I insert a small sponge in bag ''b'' to absorb the menstrual flux."</ref> and were similar external [[:wiktionary:catamenial|catamenial]] sacks of "canoe-like form",<ref name=externalsacks>{{patent|US|49915}}(1865){{patent|US|626159}}(1899)</ref> which in turn were similar to catamenial sacks which were waterproof rubber undersheet supports for absorbent pads.<ref>{{patent|US|574378}}</ref> These were made from [[india-rubber]] or [[gutta-percha]], forms of [[latex]].<ref name=externalsacks/>

== Use ==
Menstrual cups are favoured by backpackers and other travellers, as they are easy to pack and only one is needed.<ref name=wirecutter/>

Thorough washing of the cup and hands helps to avoid introducing new bacteria into the vagina, which may heighten the risk of UTIs and other infections.<ref name="Crofts">{{cite book | last1 = Crofts | first1 = T. | title = Menstruation hygiene management for schoolgirls in low-income countries | date = 2012 | url = http://www.susana.org/en/resources/library/details/1569 | publisher = [[Loughborough University|Water, Engineering and Development Center (WEDC), Loughborough University]] | location = Loughborough | access-date = 8 June 2015 | archive-date = 22 September 2017 | archive-url = https://web.archive.org/web/20170922134705/http://www.susana.org/en/resources/library/details/1569 | url-status = live }}</ref>{{medical citation needed|date=March 2024}} Disposable and reusable pads do not demand the same hand hygiene, though reusable pads also require access to water for washing out pads.

If the hands have come into contact with any chemical that directly trigger sensory receptors in the skin, such as [[menthol]] or [[capsaicin]], all traces of the chemical should be removed before touching the mucous membranes.<ref name="PN_nightmares">{{cite web |last1=Rosas |first1=Kim |title=Avoid These Menstrual Cup Dangers & Missteps |url=https://www.periodnirvana.com/menstrual-cup-nightmares/ |website=Period Nirvana |access-date=1 September 2024 |date=24 November 2020}}</ref>

A UN spec recommends that cups should not be shared; they should only ever be used by one person.<ref name=UNspec/>

===Insertion===
{{Image frame|content=
<gallery mode=packed heights=187 style="text-align:left">
Menstrual cup use 10.1177 17455065211058553-fig1 (cropped to folds).jpg|There are a variety of [[:commons:Category:Menstrual cups folds|ways to fold a menstrual cup for insertion]]; punchdown fold, 7 fold, and C fold illustrated.<ref name="quant_firmness">{{cite journal |last1=Manley |first1=H |last2=Hunt |first2=JA |last3=Santos |first3=L |last4=Breedon |first4=P |title=Comparison between menstrual cups: first step to categorization and improved safety. |journal=Women's Health |date=January 2021 |volume=17 |article-number=17455065211058553 |doi=10.1177/17455065211058553 |pmid=34798792 |pmc=8606723 }}</ref>|alt=The punchdown fold has one point on the rim turned inside-out and tucked down below the opposite side of the rim. The 7 fold has the rim flattened into a line, and both layers in parallel folded at about halfway, such that one end of the line (one folding-point of the rim) is pressed against the middle of the side of the cup. The downpressed side runs diagonally, and the other side runs horizontally, making it look like the digit seven. The C fold is the simplest and bulkiest: the rim is flattened, and then folded in half, so that the two fold-points of the rim are together. From the end, it looks like a letter C.
Menstrual cup use 10.1177 17455065211058553-fig1 (cropped to insertion single frame).jpg|The folded menstrual cup is inserted and allowed to pop open.<ref name="quant_firmness"/>|alt=Spreading the labia with the fingers of one hand and inserting the folded cup rim-first into the vagina.
Menstrual cup use 10.1177 17455065211058553-fig1 (cropped to opening).jpg|To ensure the menstrual cup is fully open and therefore creating a seal against the vaginal wall, users can run a finger around the cup to feel for bumps (a sign it is not open), or users can gently pinch and twist the menstrual cup.<ref name="quant_firmness"/>|alt=Running an index finger around the middle of the body of the cup; pinching the bottom and then twisting the cup.
</gallery>|border=no|align=right}}

{{Image frame|content=
<gallery mode=packed heights=125 style="text-align:left">
Stap1 (text cropped off).png|Inserting a thin-walled menstrual disc/ring-shaped cup.<ref name=":3">[[wikihow:Use-an-Instead-Softcup#.2FImage:Undefined_14872.png|How to use an Instead Softcup]], Wikihow</ref> Pinching the sides of the cup together and positioning it for insertion.
Stap2 cropped.png|After the pinched cup is inserted, the outer edge of the cup is tucked behind the pubic bone, opening out the cup. The inner edge of the cup must cover the cervix.
</gallery>|border=no|align=right|caption=Ring-shaped menstrual discs are worn in the same position as a contraceptive diaphragm.}}

The vagina is narrowest at the entrance and becomes wider and easier to stretch further in.<ref name="anthropometry"/> Menstrual cups are folded or compressed to insert them, and then opened out once inside. The innermost portion of the cup typically goes into the [[vaginal fornix]] (the groove around the cervix). Menstrual cups cannot [[Cervical dilation|pass through the cervix]] into the uterus.<ref name=cullins/>

The muscles of the [[pelvic floor]], which surround the vaginal entrance, are relaxed to let the cup pass. [[vaginismus|Involuntarily tensing the vaginal muscles]] can make it impossible for anything to enter the vagina without causing pain.<ref name=Anakalia/><ref name=":1"/> Many initially find insertion difficult, uncomfortable, and even painful, but learn to do it within a few cycles. There is little publicly available research on learning to use menstrual cups which compares types of cup or instructions.<ref name="Van2019" />

A bell-shaped cup is folded or pinched before being inserted into the vagina.<ref name=":13"/> There are various folding techniques for insertion; common folds include the "C" fold, the "7" fold, and the punch-down fold.<ref name="quant_firmness"/> Once inside, the cup will normally unfold automatically and seal against the vaginal wall.<ref name=":13">{{Cite web |last1=Hearn |first1=Amanda |last2=Rosas |first2=Kim |date=July 26, 2018 |title=How to Insert a Menstrual Cup |url=https://www.youtube.com/watch?v=rnuomsxjBOs&ab_channel=PutACupInIt |url-status=live |archive-url=https://web.archive.org/web/20240226170306/https://www.youtube.com/watch?v=rnuomsxjBOs&ab_channel=PutACupInIt |archive-date=February 26, 2024 |access-date=February 26, 2024 |website=YouTube}}</ref> In some cases, the user may need to twist the cup or flex the vaginal muscles to ensure the cup is fully open.<ref name=":14">{{Cite news|url=https://www.wikihow.com/index.php?title=Use-a-Menstrual-Cup&oldid=16766928|archive-url=https://web.archive.org/web/20200719064757/https://www.wikihow.com/index.php?title=Use-a-Menstrual-Cup&oldid=16766928|archive-date=July 19, 2020|title=How to Use a Menstrual Cup|date=March 2, 2015|work=wikiHow|access-date=2018-08-31|language=en}}</ref>

In practice, the rim of a bell-shaped cup generally sits in the [[vaginal fornix]], the ring-shaped hollow around the cervix.<ref name="invivoMRI"/><ref name="Anakalia"/> Some fornixes are much deeper than others.<ref name="anthropometry">{{cite journal |last1=Barnhart |first1=KT |last2=Izquierdo |first2=A |last3=Pretorius |first3=ES |last4=Shera |first4=DM |last5=Shabbout |first5=M |last6=Shaunik |first6=A |title=Baseline dimensions of the human vagina. |journal=Human Reproduction |date=June 2006 |volume=21 |issue=6 |pages=1618–22 |doi=10.1093/humrep/del022 |pmid=16478763 |url=https://academic.oup.com/humrep/article/21/6/1618/724374 |access-date=15 March 2024 |archive-date=15 April 2024 |archive-url=https://web.archive.org/web/20240415125626/https://academic.oup.com/humrep/article/21/6/1618/724374 |url-status=live |url-access=subscription }}</ref> Those with deeper fornixes may use insertion techniques such as inserting the cup partway, opening it before the rim passes the cervix, and then pushing it up into place; or they may press the cup to one side and let it open slowly, the rim slipping over the cervix.<ref name="Anakalia">{{cite web |last1=Anakalia |title=How to Choose a Menstrual Cup - For Beginners and Pros |url=https://menstrualcupreviews.net/how-to-choose-a-menstrual-cup/ |publisher=MenstrualCupReviews.net |access-date=15 March 2024 |date=9 January 2019 |archive-date=15 March 2024 |archive-url=https://web.archive.org/web/20240315202435/https://menstrualcupreviews.net/how-to-choose-a-menstrual-cup/ |url-status=live }}</ref> If correctly sized and inserted, the cup should not leak or cause any discomfort.<ref name=":5">{{Cite web|url=https://uk.lunette.com/pages/cervix|title=Vagina Anatomy - Learn Your Parts|website=Lunette UK|access-date=2018-08-31|archive-date=31 August 2018|archive-url=https://web.archive.org/web/20180831174934/https://uk.lunette.com/pages/cervix|url-status=live}}</ref> The stem should be completely inside the vagina. If it can't be positioned inside, the cup can be removed and the stem trimmed.<ref name=":13" />

Ring-shaped cups (also called menstrual discs or menstrual rings) are inserted differently than bell-shaped cups: by squeezing opposite sides of the rim together until they touch, sliding the inner end of the folded cup to the end of the vaginal canal, and tucking the outer end behind the pubic bone.<ref name=":1">{{Cite web |last=Savin |first=Jennifer |date=August 8, 2023 |title=What is a menstrual disc – and how do you use one? |url=https://www.cosmopolitan.com/uk/body/health/a44760585/menstrual-disc/ |url-status=live |archive-url=https://web.archive.org/web/20240226021936/https://www.cosmopolitan.com/uk/body/health/a44760585/menstrual-disc/ |archive-date=February 26, 2024 |access-date=February 24, 2024 |website=Cosmopolitan}}</ref><ref name="thingstoknow"/> They can be less bulky than a bell-shaped cup, no bulkier than a tampon.<ref name="JWH2011"/> Inserting a ring-shaped cup requires more knowledge of anatomy, to get the cup under and around the cervix,<ref name="disc/cup"/> not rucked up in front of it.<ref name="PN_disc_probs">{{cite web |last1=Rosas |first1=Kim |title=Menstrual Disc Problems: Common Mistakes and Fixes |url=https://www.periodnirvana.com/menstrual-disc-problems/ |website=Period Nirvana |access-date=20 March 2024 |date=17 August 2021 |archive-date=20 March 2024 |archive-url=https://web.archive.org/web/20240320190228/https://www.periodnirvana.com/menstrual-disc-problems/ |url-status=live }}</ref> Ring-shaped cups with non-circular rims are designed to be inserted with the widest, deepest part going in first. If they are inserted the wrong way around they may leak.<ref name=wirecutter/><ref name="mcr_ziggy">{{cite web |last1=Anakalia |title=Intimina Ziggy 'Cup' Menstrual Disc - Full Review |url=https://menstrualcupreviews.net/intimina-ziggy-cup-menstrual-disc-full-review/ |publisher=mentrualcupreviews.net |access-date=15 March 2024 |date=4 October 2020 |archive-date=15 March 2024 |archive-url=https://web.archive.org/web/20240315202436/https://menstrualcupreviews.net/intimina-ziggy-cup-menstrual-disc-full-review/ |url-status=live }}</ref> If there are stems or other removal aids, they should be on the end inserted last.<ref name=":1"/>

If lubricant is used for insertion, it should be [[Personal lubricant#Water-based|water-based]], as [[Personal lubricant#Silicone-based|silicone lubricant]] can be damaging to the silicone.<ref>{{Cite web |last=Rosas |first=Kim |date=2022-06-06 |title=How to Insert a Menstrual Cup for Beginners |url=https://www.periodnirvana.com/tips-for-your-first-time-easy-menstrual-cup-insertion/ |archive-url=https://web.archive.org/web/20231109220257/https://www.periodnirvana.com/tips-for-your-first-time-easy-menstrual-cup-insertion/ |archive-date=2023-11-09 |access-date=2023-11-09 |website=Period Nirvana |language=en-US}}</ref>

=== Wear ===
{{Image frame|content=
<gallery mode=packed heights=200>
File:Menstruationstasse im Roentgenbild 28W - CR pa - 001.jpg|An X-ray that shows a bell-shaped menstrual cup in place. The cervix can be seen in the mouth of the cup; the cup rim is in the [[vaginal fornix]]. Bell-shaped cups have the same shape when in use inside the body as outside, and create an empty space (black on the X-ray).
File:MRI with menstrual cup Frph-05-1162746-g005.jpg|An [[Magnetic resonance image|MRI]] showing a bell-shaped menstrual cup in place; cup in blue, [[uterus]] in red. The ecto[[cervix]] (the portion of the cervix that protrudes into the vagina) sits inside the cup. [[Sagittal plane]].
</gallery>|border=no|align=right|caption=Many drawings show bell-shaped cups located far down the vagina, but this contradicts [[in-vivo]] imaging.<ref name="invivoMRI"/>}}

A bell-shaped cup may protrude far enough to be uncomfortable if it is too long. It may press too firmly against the bladder, causing discomfort, frequent urination, or difficulty urinating, if it is too firm, or the wrong shape.<ref name="Anakalia"/> A bell-shaped cup may leak if it is not inserted correctly, and does not pop open completely and seal against the walls of the vagina. Some factors mentioned in association with leakage included [[Heavy menstrual bleeding|menorrhagia]], unusual [[anatomy]] of the [[uterus]], need for a larger size of menstrual cup, and incorrect placement of the menstrual cup, or that it had filled to capacity.<ref name="Van2019"/> However, a proper seal may continue to contain fluid in the upper vagina even if the cup is full.{{citation needed|date=February 2023}}

While many diagrams show bell-shaped menstrual cups very low in the vagina, with the vagina gaping open, in-vivo imaging shows that the cups sit high, with their rim around the cervix, and the vagina squishes shut below the cup, sealing it inside the body.<ref name="invivoMRI"/>

If a ring-shaped cup pops out at the outermost edge, either the innermost edge got caught on near side of the cervix rather than tucked into the fornix behind it, or it is too big, or the outermost edge hasn't been tucked behind the public bone firmly enough. In either any case it will leak. If it comes loose and starts to slide out when using the toilet, or leaks on exertion (when exercising, coughing, or sneezing), it is too large or too small.<ref name="PN_disc_probs"/> Some deliberately choose a ring-shaped cup which will leak when they deliberately bear down on it, but not at any other time.<ref name="autodump"/><ref name="cosmop"/>

{{clear}}

=== Emptying ===
[[File:Cathole.png|thumb|upright=0.7|Menstrual cups can be emptied into a [[cathole]]]]
It is possible to deliberately empty a ring-shaped menstrual disc by muscular effort, without removing it (provided it is of a fairly soft material, and the right size). This is done in a suitable location, such as when sitting on a toilet. Bell-shaped cups must be removed to empty them.<ref name="autodump">{{cite web |last1=Rosas |first1=Kim |title=Menstrual Disc Auto-Dumping: Emptying Your Disc |url=https://www.periodnirvana.com/menstrual-disc-auto-dumping-explained-3/ |website=Period Nirvana |date=11 October 2020 |access-date=11 March 2024 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311191743/https://www.periodnirvana.com/menstrual-disc-auto-dumping-explained-3/ |url-status=live }}</ref><ref name="cosmop">{{cite news |last1=Savin |first1=Jennifer |title=Menstrual discs are officially the best period product for a heavy flow... |url=https://www.cosmopolitan.com/uk/body/health/a44760585/menstrual-disc/ |work=Cosmopolitan |date=8 August 2023 |access-date=26 February 2024 |archive-date=26 February 2024 |archive-url=https://web.archive.org/web/20240226021936/https://www.cosmopolitan.com/uk/body/health/a44760585/menstrual-disc/ |url-status=live }}</ref>

The cup is emptied after 4–12 hours of use (or when it is full).<ref name=Lancet_review/> Leaving the cup in for at least 3–4 hours allows the menstrual fluid to provide some lubrication.<ref name="soch1st"/>

If sewers are available, menstrual cups can be emptied into a flush toilet, or sink, bath, or shower drain, and the drain rinsed with water. They can also be emptied into a pit latrine.<ref name="path_cleaning_review"/><ref name="PN_where_empty">{{cite web |last1=Rosas |first1=Kim |title=Where to Empty Your Menstrual Cup (While at Home) |url=https://www.periodnirvana.com/where-is-the-best-place-to-empty-a-menstrual-cup/ |website=Period Nirvana |access-date=1 September 2024 |date=27 May 2022}}</ref>

When using a [[urine-diverting dry toilet]], menstrual blood can be emptied into the part that receives the feces. If any menstrual blood falls into the funnel for urine, it can be rinsed away with water.<ref>WECF (2006). [http://www.susana.org/en/resources/library/details/426 Ecological sanitation and hygienic considerations for women - Fact Sheet] {{Webarchive|url=https://web.archive.org/web/20170411140027/http://www.susana.org/en/resources/library/details/426 |date=11 April 2017 }}. Women in Europe for a Common Future, Netherlands and Germany</ref>

In the absence of other facilities, menstrual fluid can be emptied into a [[cathole]]. This is a single-use hole {{convert|6|to|8|in|cm}} deep, more than {{convert|200|ft|m|-1}} from water (and frequented areas like trails or campsites), ideally dug in organic soil, in an area where the waste will break down fast. Water used to rinse the cup can also be disposed of in the cathole, which is then refilled and concealed.<ref>{{cite web |last1=Maiers |first1=Bobbi |date=2021-04-15 |first2=Alicia |last2=MacLeay |title=Human Waste Disposal in the Backcountry: How to pee and poop in the woods - Trailspace |url=https://www.trailspace.com/articles/backcountry-waste-disposal.html |website=www.trailspace.com |access-date=1 September 2024 |language=en |archive-date=28 April 2024 |archive-url=https://web.archive.org/web/20240428204421/https://www.trailspace.com/articles/backcountry-waste-disposal.html |url-status=live }}</ref>

===Removal===
{{Gallery| align=right| width = 200
|File:Menstrual cup use 10.1177 17455065211058553-fig1 (cropped to removal).jpg
|To remove a bell-shaped cup, the seal is broken by running a finger cup the side of the menstrual cup, or pinching the base of the vessel. The cup is then slowly and gently removed, shifting the menstrual cup from side to side.<ref name="quant_firmness"/>
|alt1=
|File:Gestion menstrual copita copa menstrual menstruación periodicas 02.jpg
|A filled menstrual cup after use. With practice, it is possible to remove a bell-shaped cup without spilling or bloodying the hands.
|alt2=
|File:Stap4 (cropped text off).png
|Hooking a finger under the rim of a ring-shaped cup to remove it; the finger can also be hooked over the rim, or the rim can be pinched.
|alt3=
}}
[[File:Magdeburg hemispheres, drawing from Fotothek 0005669.jpg|thumb|Pulling against a vacuum [[Magdeburg hemispheres|does not work]]; the seal must be broken before removing a bell-shaped cup.]]
Many initially find removal difficult, uncomfortable, and even painful, but learn to do it without problems within a few cycles.<ref name="Van2019" />

The muscles of the [[pelvic floor]] are kept relaxed, to allow the cup to pass out [[Urogenital hiatus|through them]].<ref name=wirecutter/> Techniques like squatting, putting a leg up on the toilet seat, spreading the knees, and bearing down on the cup as if giving birth are sometimes used to make removal easier.<ref name="soch1st">{{cite web |last1=Shastry |first1=Sharmada |title=Ultimate Guide On How To Use Menstrual Cup-Effectively |url=https://www.sochgreen.com/how-to-use-menstrual-cup-for-the-first-time/ |access-date=16 March 2024 |date=14 November 2020 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316202709/https://www.sochgreen.com/how-to-use-menstrual-cup-for-the-first-time/ |url-status=live }}</ref><ref name=cullins/><ref name="pn_disc_insert_remove"/> Because [[tenting effect|vaginal tenting]] can make the cup harder to remove, some manufacturers recommend waiting at least an hour after sex before removal.<ref name="nixitFAQ">{{cite web |title=FAQs |url=https://nixit.ca/pages/faqs |website=nixit canada |publisher=Nixit Mentstrual Cups |access-date=16 March 2024 |language=en |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316211915/https://nixit.ca/pages/faqs |url-status=live }}</ref>

Slow removal and a firm grip avoid dropping the cup;<ref name="pn_disc_insert_remove"/> experience, time and privacy also help.<ref name=Lancet_review/> Dropping the cup can contaminate it (see [[#Cleaning|cleaning]], below).<ref name=Lancet_review/> <!-- prob need medrs for boiling after dropping it in the toilet, https://www.periodnirvana.com/pooping-menstrual-cup/-->If a cup is removed or emptied over a [[pit latrine]], it may fall in and be unretrievable.<ref name="path_cleaning_review"/>

A bell-shaped cup is removed by reaching up to its stem to find the base. Simply pulling on the stem does not break the seal, and yanking on it can cause pain. To release the seal, the base of the cup is pinched, or a finger is placed alongside the cup.<ref name=":5"/><ref name=wirecutter/> The exception is two-part cups with separate stems; those ''can'' be pulled out to break the seal.<ref name="pn_2-part">{{cite web |last1=Rosas |first1=Kim |title=FLEX Cup Review {{!}} Removes like a tampon |url=https://www.periodnirvana.com/flex-cup-review/ |website=Period Nirvana |date=21 December 2020 |access-date=16 March 2024 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316202708/https://www.periodnirvana.com/flex-cup-review/ |url-status=live }}</ref> The shape of the (one-part) stem thus has little effect on how easy the cup is to remove, and many people trim the stem right off for comfort.<ref name=wirecutter/> The cup is removed slowly;<ref name=":5"/><ref name=wirecutter/> rocking or wriggling it gently may help.<ref name=cullins/> Some fold the cup in a "C" fold before removal, to break the seal and reduce the bulk; folding the cup inside the body is generally more difficult than folding it outside.

A cup can be removed over a toilet, bath, or shower to catch spills.<ref>{{Cite web |last1=Hearn |first1=Amanda |last2=Rosas |first2=Kim |date=July 26, 2018 |title=How to Remove a Menstrual Cup |url=https://www.youtube.com/watch?v=SBZF0vHSf0c&ab_channel=PutACupInIt |url-status=live |archive-url=https://web.archive.org/web/20240226171307/https://www.youtube.com/watch?v=SBZF0vHSf0c&ab_channel=PutACupInIt |archive-date=February 26, 2024 |access-date=February 26, 2024 |website=YouTube}}</ref><ref name="PN_where_empty"/> Removal becomes less messy with practice, and it is possible to consistently remove bell-shaped cup without spilling, by keeping it upright.<ref name="mess-free">{{cite web |last1=Rosas |first1=Kim |title=Remove Your Menstrual Cup Mess-Free {{!}} It's not a blood bath, I promise |url=https://www.periodnirvana.com/remove-menstrual-cup-mess-free/ |website=Period Nirvana |date=4 February 2022 |access-date=11 March 2024 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311191743/https://www.periodnirvana.com/remove-menstrual-cup-mess-free/ |url-status=live }}</ref>{{better source needed|date=March 2024}} If it is necessary to track the amount of menses produced (e.g., for medical reasons), a bell-shaped cup allows one to do so accurately before emptying.<ref name="HMB">{{cite journal |last1=DeLoughery |first1=Emma |last2=Colwill |first2=Alyssa C. |last3=Edelman |first3=Alison |last4=Bannow |first4=Bethany Samuelson |title=Red blood cell capacity of modern menstrual products: considerations for assessing heavy menstrual bleeding |journal=BMJ Sexual & Reproductive Health |date=1 January 2024 |volume=50 |issue=1 |pages=21–26 |doi=10.1136/bmjsrh-2023-201895 |pmid=37550075 |pmc=10847380 |language=en |issn=2515-1991}}</ref>

Ring-shaped menstrual cups are removed by hooking the rim with a finger (from either side), or by pinching it with multiple fingers and pulling. Some ring-shaped cups have a dimple in the bowl, to make it easier to hook the rim from below. Some also have stems, but contrary to bell-shaped cups, these stems attach to the rim of the cup, and can be pulled to break the seal. Others have pull loops that fold flat against the bowl, which can also be pulled to remove.<ref name=pn_disc_removal>{{Cite web |last=Rosas |first=Kim |date=January 24, 2023 |title=Menstrual Disc Removal {{!}} Step-by-Step Guide |url=https://www.periodnirvana.com/step-by-step-how-to-remove-a-menstrual-disc/ |url-status=live |archive-url=https://web.archive.org/web/20240226022637/https://www.periodnirvana.com/step-by-step-how-to-remove-a-menstrual-disc/ |archive-date=February 26, 2024 |access-date=February 25, 2024 |website=Period Nirvana}}</ref> Removing ring-shaped cups is typically done over a toilet in case of spilling; the softer bowl squishes flat during removal, making it very difficult not to spill any menstruum.<ref name="pn_disc_insert_remove">{{cite web |last1=Rosas |first1=Kim |title=How to Insert a Menstrual Disc and How to Remove It |url=https://www.periodnirvana.com/how-to-insert-and-remove-a-menstrual-disc/ |website=Period Nirvana |date=1 February 2021 |access-date=16 March 2024 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316202708/https://www.periodnirvana.com/how-to-insert-and-remove-a-menstrual-disc/ |url-status=live }}</ref><ref name=pn_disc_removal/> Removal aids like pull loops can make ring-shaped cups easier to remove without spilling, but they still tend to be messier than bell-shaped cups.<ref name="PN_divadisc_review">{{cite web |last1=Rosas |first1=Kim |title=Diva Disc Review {{!}} First Look At The New Reusable Menstrual Disc From DivaCup |url=https://www.periodnirvana.com/diva-disc-review/ |website=Period Nirvana |access-date=1 September 2024 |date=15 September 2022}}</ref>

{{clear}}
=== Cleaning ===
[[File:Boiling a menstrual cup2.jpg|right|thumb|alt=picture of a bell-shaped menstrual cup, covered in simmering water in a stainless cooking pot on a hob|Almost all manufacturers recommend boiling new cups before the first use.<ref name="path_cleaning_review"/>]]

There is little published or independent research on how to clean menstrual cups. Manufacturers generally provide cleaning instructions, but they differ widely. Manufacturers did not provide any evidence validating or giving a rationale for the various cleaning instructions, as of 2022.<ref name="path_cleaning_review"/>  A UN specification says that "The cup must be washed frequently in clean, boiling water as per manufacturer's instructions."<ref name=UNspec/>

In response to the 2022 review of manufacturer's recommendations (next section), which said there was no published evidence on how well cleaning methods work,<ref name="path_cleaning_review"/> a single small [[in-vitro]] study was done to compare cleaning methods.

====Cleaning study====
{{Image frame|content=
<gallery mode=packed style="text-align:left" heights=165>
File:Washing a menstrual cup under a stream of fresh water in a sink 3.jpg|Rinsing a cup under cool, clean running water in a sink. Hot water speeds [[coagulation]] and can set bloodstains.
File:Handmade soap cropped and simplified.jpg|Soap is effective at cleaning the cup, but all soap residues must be rinsed off,<ref name="cleaning_test"/> so scented or moisturizing soaps are not recommended.<ref name="path_cleaning_review"/>
File:北日本カコー株式会社 (19579133484) (tightly cropped).jpg|Pouring just-boiled water into a ceramic mug. [[Steeping]] menstrual cups is very effective.<ref name="cleaning_test"/>
File:Menstruationstasse (DivaCup) 04 (cropped).jpg|Raised text and other unsmooth features provide more purchase for bacteria.<ref name="cleaning_test"/>
</gallery>|border=no|align=right}}

A single small [[in-vitro]] study (using human blood, but incubation outside the body) compared four cleaning treatments:
# cold water (cup rubbed with fingers under running water for 30 seconds)
# cold water and liquid soap (used instead of the more common bar soap so that the quantity could be more easily measured)
# cold water followed by [[steeping]] (putting the cup in a ceramic mug and pouring water over it as soon as the water boiled, then steeping for 5 min with the mug covered by a small plate; after five minutes, the water in the mug was still above 75 Celsius)
# cold water and soap followed by steeping
It did not compare boiling to steeping, or steeping after [[ISO_3103#Criticism|warming the mug]]. All of the methods decreased the bacterial load of the cups, with steeping having a bigger individual effect than soap; when using all three cleaning methods on cups (the fourth treatment), the authors were unable to culture bacteria from them. Just rinsing and steeping, with no soap, had very similar or identical effects.<ref name="cleaning_test"/>

The authors recommended using as many of the cleaning methods as possible, but using soap only if it can be thoroughly washed off, as soap residue can irritate the vagina. They pointed out the need for ''in-vivo'' studies, looking at real health outcomes, and the need for studies on more than the single model of cup they tested.<ref name="cleaning_test">{{cite journal |last1=Wunsch |first1=N |last2=Green |first2=SJ |last3=Adam |first3=S |last4=Hampton |first4=J |last5=Phillips-Howard |first5=PA |last6=Mehta |first6=SD |title=In Vitro Study to Assess Effective Cleaning Techniques for Removing Staphylococcus aureus from Menstrual Cups. |journal=International Journal of Environmental Research and Public Health |date=27 January 2022 |volume=19 |issue=3 |page=1450 |doi=10.3390/ijerph19031450 |doi-access=free |pmid=35162481|pmc=8835062 }}</ref>

====Review of manufacturers' recommendations====
A 2022 review stated that "Publicly accessible evidence is needed to create consumer confidence in the recommended cleaning practices... nearly all menstrual cup manufacturers fail to provide any publicly available independent evidence that supports their recommended cleaning practices". The review found no standards or guidelines for menstrual cup cleaning practices, and urged independent research to establish a normative standard.<ref name="path_cleaning_review"/>
{| class="wikitable mw-collapsible mw-collapsed floatright"
|+ A table of other cleaning recommendations and counterrecommendations
|-
! Method !! Before first use !! Within cycle !! Between cycles || Variations
|-
| not cleaning it at all, just reinserting it as-is
| || has been suggested as a stopgap measure by at least one manufacturer.<ref name="ruby_clean"/> ||  ||
|-
| rinsing it in water only
| || 10/24 manufacturers in 2022 recommended this, four of them as an alternative to using soap<ref name="path_cleaning_review"/> || ||rinsing in cold water at least initially to inhibit [[blood residue|bloodstains]];<ref name=nixitFAQ/> rinsing it in a sink,<ref name="ruby_clean"/> or using a water bottle,<ref name="ruby_clean"/> especially in areas with no running water. Some users carry a bottle of clean water to rinse the cup with when on the road.<ref name="path_cleaning_review"/>
|-
| washing it in mild [[soap]] and water
| || 17/24 manufacturers in 2022 recommended this<ref name="path_cleaning_review"/> 1/24 counterecommended soap, and 1/24 said soap was unnecessary.<ref name="path_cleaning_review"/> ||  ||14/17 recommended unscented, oil-free, water-based, nonantibacterial soap. Some counterecommend [[castile soap]], dish soap, and heavy-duty facial cleanser.<ref name="path_cleaning_review"/> The scent left by soap is a residue; moisturizing soaps also leave a residue.{{Citation needed|date=March 2024}}
|-
| washing it in a proprietary menstrual-cup-cleaning solution and water
| || 9/17 manufacturers in 2022 recommended this as an optional alternative to using soap.<ref name="path_cleaning_review"/> ||  ||
|-
| wiping it off, with tissue or another dry wipe, and reinserting it
| || 8/24 manufacturers in 2022 recommended this.<ref name="path_cleaning_review"/> ||  ||if using toilet paper, blotting instead of rubbing to stop the paper from disintegrating.<ref name="ruby_clean">{{Cite web |title=How to Clean a Menstrual Cup in a Public Bathroom: 6 Ways |url=https://rubycup.com/blogs/articles/clean-menstrual-cup-public-bathroom |url-status=live |archive-url=https://web.archive.org/web/20240226165437/https://rubycup.com/blogs/articles/clean-menstrual-cup-public-bathroom |archive-date=February 26, 2024 |access-date=February 25, 2024 |website=Ruby Cup |date=7 October 2021 }}</ref>
|-
| wiping it with a disposable wipe
| 1/24 manufacturers recommended wiping with a proprietary soap-based wipe in 2022.<ref name="path_cleaning_review"/> ||  || 8/24 manufacturers in 2022 recommended a proprietary wipe.<ref name="path_cleaning_review"/> || Some distributors market wipes intended specifically for cleaning menstrual cups; they may contain a variety of active ingredients, including purified water, soap, or [[denatured alcohol]].<ref name="path_cleaning_review"/> Non-cup-specific wipes sometimes used include isopropyl alcohol disposable wipe (not the sort with a moisturizer, as that leaves a residue), or [[wet wipe|wipe]]s such as "feminine wipes" or hypoallergenic baby wipes;<ref name=cullins>{{Cite web |last1=Dougher |first1=Kelly |last2=Thompson |first2=Kirsten |last3=Cullins |first3=Vanessa |date=March 12, 2020 |title=What is a Menstrual Cup? How to Use It, Remove It, and More |url=https://www.teenvogue.com/story/menstrual-cups-everything-you-need-to-know |url-status=live |archive-url=https://web.archive.org/web/20230605142317/https://www.teenvogue.com/story/menstrual-cups-everything-you-need-to-know |archive-date=June 5, 2023 |access-date=February 25, 2024 |website=Teen Vogue}}</ref> some types of wipes have moisturizing lotions, preservatives, or other residues.{{citation needed|date=March 2024}} 3/24 manufacturers ''counter''recommended cleaning cups with isopropyl alcohol in 2022; 1/24 counterecommended alcohol-based wipes.<ref name="path_cleaning_review"/>
|-
| boiling the cup or [[steeping]], covered, in freshly boiled water (like some types of tea)
| In 2022, 18/24 manufacturers recommended this. 7/18 recommended five minutes or less, 7/18 recommended 5–10 minutes, one recommended 10-20 min, and 2/18 recommended over twenty minutes, with one last manufacturer not suggesting a time.<ref name="path_cleaning_review"/> || 3/24 manufacturers recommended this in 2022; all offered alternatives<ref name="path_cleaning_review"/> || 23/24 manufacturers recommended this or noted it as optional in 2022. 11/23 recommended five minutes or less, 5/23 recommended 5–10 minutes, and 2/23 recommended over twenty minutes, with 5/23 manufacturer not suggesting a time.<ref name="path_cleaning_review"/> || Almost all manufacturers recommend boiling before first use. Almost all manufacturers recommend boiling or steeping in boiling water between cycles, as mandatory or as an option, and most users do boil their cups.<ref name="path_cleaning_review"/> 2/24 recommended boiling times of no more than five minutes, and 1/24, <10min. Long boiling can damage the cup, and boiling it dry can melt it.<ref name="path_cleaning_review"/> {{refn|5min,<ref name=nixitFAQ/>}} Kitchen facilities may lack privacy. Distributors seldom provide a boiling pot; people unable to afford a cup-boiling container sometimes used containers which might leave a harmful residue, like old paint cans.<ref name="path_cleaning_review"/>
|-
| steaming the cup in a menstrual-cup steamer<ref name="path_cleaning_review"/>
| || 1/24 manufacturers recommended this in 2022.<ref name="path_cleaning_review"/> || 1/24 manufacturers in 2022 recommended this.<ref name="path_cleaning_review"/> ||Takes 8–10 minutes.<ref name="path_cleaning_review"/> Steamer must be cleaned and dried afterwards,{{citation needed|date=March 2024}} USB steamers are not affordable in many lower-and middle-income countries.<ref name="path_cleaning_review"/>
|-
| microwaving
| 1/24  recommended microwaving for five minute with water in a proprietary container ||  || 9/24 manufacturers recommended this in 2022.<ref name="path_cleaning_review"/> || Some manufacturers recommend, others counterrecommend; one recommended microwaving for five minute with water in a proprietary container, others recommend boiling in water in a microwave. This is not workable in lower-income houses that do not have microwaves.<ref name="path_cleaning_review"/> Microwaving in a breast-pump sterilization bag is also sometimes practiced.{{citation needed|date=March 2024}}
|-
| washing in the dishwasher
| ||  ||  || 4/24 manufacturers ''counter''recommended cleaning cups in the dishwasher in 2022.<ref name="path_cleaning_review"/>
|-
| vinegar solution
| 1/24 manufacturers in 2022 recommended boiling in a 1:9 solution.<ref name="path_cleaning_review"/> ||  || 1/24 manufacturers in 2022 recommended soaking in vinegar.<ref name="path_cleaning_review"/> || 3/24 manufacturers ''counter''recommended cleaning cups with vinegar in 2022.<ref name="path_cleaning_review"/>
|-
| soaking with a sterilizing tablet (generally [[sodium dichloroisocyanurate]], used for baby bottles and breast pump equipment)
| 4/24 manufacturers in 2022 recommended this.<ref name="path_cleaning_review"/> || 1/24 manufacturers recommended this in 2022.<ref name="path_cleaning_review"/> || 9/24 manufacturers recommended this in 2022.<ref name="path_cleaning_review"/>
|-
| petroleum-based lubricants and essential oils
| ||  ||  || 6/24 manufacturers ''counter''recommended using essential oils with cups in 2022; 5/24 countereccomended petroleum lubricants.<ref name="path_cleaning_review"/>
|-
| "corrosive" or "harsh" cleaning chemicals
| ||  ||  || 6/24 manufacturers in 2022 counterreccomended this, but none of them were specific about what cleaners were to be avoided.
|-
| baking soda
| ||  ||  || 2/24 counterrecommended using baking soda in 2022; none recommended it.<ref name="path_cleaning_review"/>
|-
| soaking in [[hydrogen peroxide]] solution
| ||  ||  || Some manufacturers recommend, others (3/24) counterrecommended any sort of [[bleach]] in 2022.<ref name="path_cleaning_review"/>
|-
| soaking in [[isopropyl alcohol]] solution
| In 2022, one manufacturer recommended soaking thus for 10 minutes.<ref name="path_cleaning_review"/>||  || 2/24 manufacturers in 2022 recommended this.<ref name="path_cleaning_review"/> || 3/24 manufacturers ''counter''recommended cleaning cups with isopropyl alcohol in 2022.
|-
| ultraviolet light irradiation
| ||  ||  || Some manufacturers recommend.<ref name="path_cleaning_review"/>
|-
| ozone generation
| ||  ||  || Some manufacturers recommend.<ref name="path_cleaning_review"/>
|-
| a cup with a mechanically [[superhydrophobic surface]]
| N/A || N/A || N/A || A "microtopographic design that incorporates micron-scale thick lubricant" ([[polydimethylsiloxane]]) in a "replenishing slippery surface"; the manufacturer says that week-old bloodstains can be wiped off, and that rinsing in water and wiping are the only cleaning needed.<ref name="path_cleaning_review"/><ref name="Bfree cup features">{{cite web |title=Bfree cup features |url=https://bfreecup.com/pages/bfree-cup-features |website=bfree cup. |language=en |access-date=17 March 2024 |archive-date=17 March 2024 |archive-url=https://web.archive.org/web/20240317025401/https://bfreecup.com/pages/bfree-cup-features |url-status=live }}</ref>
|}

The most common recommendations are:
*boiling a new cup before using it for the first time, for about five minutes
*when a menstrual cup is removed and emptied, it is generally cleaned before it is reinserted; the most common recommendations were:
**washing with water and a "mild" soap, for preference
**rinsing in water (second choice)
**wiping with a clean, dry wipe such as toilet tissue (third choice)
*boiling or [[steeping]] a cup between menstrual cycles for about five minutes.
Most manufacturers recommended using water and soap if readily available. Many counterrecommend scented soaps and soaps [[soapmaking|made with an excess of oil or fat]]<ref name="path_cleaning_review">{{cite web |title=Menstrual cup cleaning practices: A mixed methods study of published instructions and key informant interviews |date=May 2021 |url=https://www.path.org/our-impact/resources/menstrual-cup-cleaning-practices-mixed-methods-study-published-instructions-and-key-informant-interviews/ |access-date=17 March 2024 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316014313/https://www.path.org/our-impact/resources/menstrual-cup-cleaning-practices-mixed-methods-study-published-instructions-and-key-informant-interviews/ |url-status=live }}</ref> (in order to create [[Moisturizer|moisturizing]] soap<ref>{{cite web |title=The Process of Making Soap |url=http://edtech.mcc.edu/~abaker/comw100/finalproject/process.html |website=edtech.mcc.edu |access-date=8 March 2020 |archive-date=15 July 2019 |archive-url=https://web.archive.org/web/20190715192100/http://edtech.mcc.edu/~abaker/comw100/finalproject/process.html }}</ref>). Scents and moisturizers are designed to remain as residues on the hands after washing.

Some manufacturers sell and recommend proprietary cleaning products.<ref name=wirecutter/><ref name="path_cleaning_review"/> These are not considered necessary.<ref name="cleaning_test"/><ref name=wirecutter/>{{better source needed|date=March 2024}}

====Containers for steeping and boiling====
{{Image frame|content=
<gallery mode=packed heights=200>
File:Irish Coffee Glass (Mug).svg|Mugs may be used to steep menstrual cups.
File:YellowGaiwanLidOff.jpg|The container is covered with a plate or lid (like the lid of this [[gaiwan]]) during steeping.
File:Fasolka po bretońsku, 2010.png|Commercial [[canned food]], in metal and glass cans. Both types of can have been used for sterilizing menstrual cups. Some containers are likely to be unsafe to use for this purpose.
File:Mason jar array.jpg|[[Mason jar]]s (without their lids) are also used to boil and steep cups.
</gallery>|border=no|align=right}}

A dedicated menstrual-cup-cleaning pot may be too expensive, and use of kitchen pots socially unacceptable. Alternatives like used paint cans may contain harmful substances.<ref name="path_cleaning_review"/> [[Steel can|Food cans]] are used; these hold their temperature better than an unwarmed ceramic mug for steeping,<ref name="cleaning_test"/> but there is no data on the safety of tinned or plastic-coated food cans for this use.<ref>There is discussion of the food cans contaminating the canned food, but none on their reuse to boil anything.
*FDA measuring lead leaching from food cans:
**{{cite web |title=It's time to eliminate lead from tin coating and solder on metal food cans - EDF Health |url=https://blogs.edf.org/health/2021/01/11/its-time-to-eliminate-lead-from-tin-coating-and-solder-on-metal-food-cans/ |website=blogs.edf.org |access-date=29 March 2024 |date=11 January 2021 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329192156/https://blogs.edf.org/health/2021/01/11/its-time-to-eliminate-lead-from-tin-coating-and-solder-on-metal-food-cans/ |url-status=live }}
**{{cite web |title=Latest federal data on lead in food suggests progress made in 2016 was fleeting - EDF Health |url=https://blogs.edf.org/health/2019/10/03/latest-federal-data-lead-food-progress-fleeting/ |website=blogs.edf.org |date=3 October 2019 |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329192706/https://blogs.edf.org/health/2019/10/03/latest-federal-data-lead-food-progress-fleeting/ |url-status=live }}
*Review finding canned food consumption is a predictor of urine BPA{{cite journal |last1=Pacyga |first1=DC |last2=Sathyanarayana |first2=S |last3=Strakovsky |first3=RS |title=Dietary Predictors of Phthalate and Bisphenol Exposures in Pregnant Women. |journal=Advances in Nutrition |date=1 September 2019 |volume=10 |issue=5 |pages=803–815 |doi=10.1093/advances/nmz029 |pmid=31144713 |pmc=6743849 }}
*Market survey of the materials in can linings, including BPA-free substitutes.{{cite web |title=Buyer Beware: Toxic BPA and regrettable substitutes found in the linings of canned food |url=http://www.toxicfoodcans.org/wp-content/uploads/2016/03/BPA-BuyerBeware.pdf |archive-url=https://web.archive.org/web/20160801025133/http://www.toxicfoodcans.org/wp-content/uploads/2016/03/BPA-BuyerBeware.pdf |archive-date=2016-08-01 }}
*Review discussing migration of contaminants in canned food from can materials {{cite journal |last1=Zheng |first1=J |last2=Tian |first2=L |last3=Bayen |first3=S |title=Chemical contaminants in canned food and can-packaged food: a review. |journal=Critical Reviews in Food Science and Nutrition |date=2023 |volume=63 |issue=16 |pages=2687–2718 |doi=10.1080/10408398.2021.1980369 |pmid=34583591}}
*Update on can lining changes {{cite web |last1=Wang |first1=Karen |title=Is Canned Food Safe from BPA Now? |url=https://ceh.org/yourhealth/is-canned-food-safe-from-bpa-now/ |website=Center for Environmental Health |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329190032/https://ceh.org/yourhealth/is-canned-food-safe-from-bpa-now/ |url-status=live }}
*Industry explainer{{cite web |title=Innovations in Food Cans |url=https://www.cancentral.com/foodcans/innovations-food-cans/ |website=Can Manufacturers Institute - Can Central |publisher=Can Manufacturers Institute |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329184532/https://www.cancentral.com/foodcans/innovations-food-cans/ |url-status=live }}
**an industry-run market survey showing only some cans imported to the US now contain BPA, as of 2020.{{cite web |url=https://www.cancentral.com/wp-content/uploads/2023/01/CMI-Washington-State-Canned-Food-Market-Basket-Report-Raw-Data.pdf |website=Can Manufacturers Institute - Can Central |publisher=Can Manufacturers Institute |date=2020 |title=CMI Washington State Canned Food Market Basket Survey |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329184533/https://www.cancentral.com/wp-content/uploads/2023/01/CMI-Washington-State-Canned-Food-Market-Basket-Report-Raw-Data.pdf |url-status=live }}
*Washington State, in the US, looking at improving the safety of can linings.{{cite web |title=Department of Ecology - Committees, Boards, and Workgroups |url=https://www.ezview.wa.gov/site/alias__1962/37555/safer_products_for_washington.aspx |website=www.ezview.wa.gov |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329184532/https://www.ezview.wa.gov/site/alias__1962/37555/safer_products_for_washington.aspx |url-status=live }}, and specifically {{cite web |title=Priority Consumer Products Draft Report to the Legislature: Safer Products for Washington Implementation Phase 2 |url=https://apps.ecology.wa.gov/publications/summarypages/2004004.html |website=apps.ecology.wa.gov |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329184532/https://apps.ecology.wa.gov/publications/summarypages/2004004.html |url-status=live }}</ref> [[Mason jar]]s made for [[home canning]] are heatproof and designed to be sterilized by boiling; they have been used to steep-sterilize menstrual cups.<ref>{{cite web |title=How to Clean and Store a Menstrual Cup |url=https://phiacare.com/blogs/health-wellness/how-to-clean-and-store-a-menstrual-cup |website=Phia |language=en |date=7 October 2021 |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329200246/https://phiacare.com/blogs/health-wellness/how-to-clean-and-store-a-menstrual-cup |url-status=live }}</ref> They have also been used (presumably unsealed) for storage.<ref>{{cite web |last1=Haggerty |first1=Alyson |title=Ten Tips and Tricks for Using a Menstrual Cup for the First Time |url=https://neworleansmom.com/health-wellness/ten-tips-and-tricks-for-using-a-menstrual-cup-for-the-first-time/ |website=New Orleans Mom |date=2 February 2021 |access-date=29 March 2024 |archive-date=29 March 2024 |archive-url=https://web.archive.org/web/20240329200245/https://neworleansmom.com/health-wellness/ten-tips-and-tricks-for-using-a-menstrual-cup-for-the-first-time/ |url-status=live }}</ref> Mugs have also been used.<ref name="cleaning_test"/> USB-powered sterilizers and proprietary menstrual cup cleaning solutions are not accessible to poorer users.<ref name="path_cleaning_review"/>

Some menstrual cups come with cleaning containers; the cup is intended to be steeped in the container with boiling water for five minutes or microwaved in the container with water for 3–5 minutes. Containers are made from a medical-grade silicone or polypropylene.<ref name="path_cleaning_review"/>

====In practice====
A South African study found that 93% used tap water when cleaning their cups at home, but only 32-44% rinsed their cups with tap water outside the home; when water was not available, many women left their cups in all day.<ref name="cleaning_test"/>

In situations where clean water is hard to get or in short supply, it may be difficult to clean the cup with water. Reusable alternatives, like washing rags, may take more water.<ref name="path_cleaning_review"/> A lack of soap also presents a problem in some developing countries.<ref name=":0">{{Cite journal |vauthors=Mason L, Laserson K, Oruko K, Nyothach E, Alexander K, Odhiambo F, Eleveld A, Isiye E, Ngere I, Omoto J, Mohammed A |year=2015 |title=Adolescent schoolgirls' experiences of menstrual cups and pads in rural western Kenya: a qualitative study |journal=Waterlines |volume=34 |issue=1 |pages=15–30 |doi=10.3362/1756-3488.2015.003|s2cid=72846874 }}</ref>

Washing a menstrual cup in a sink at a [[public toilet]] can pose problems, as the [[handwashing]] sinks are often in a public space rather than in the toilet cubicle.<ref>{{Cite web |last=Telfer |first=Nicole |date=January 2, 2019 |title=Menstrual cups: questions, myths, and misconceptions |url=https://helloclue.com/articles/culture/menstrual-cups-questions-myths-and-misconceptions |url-status=live |archive-url=https://web.archive.org/web/20240226165229/https://helloclue.com/articles/culture/menstrual-cups-questions-myths-and-misconceptions |archive-date=February 26, 2024 |access-date=February 25, 2024 |website=Clue}}</ref> Accessible loos generally have sinks that can be reached from the toilet, but they may be needed by people with limited mobility.<ref name="ruby_clean"/> Some users do not empty cups in public toilets; if they only empty the cup twice a day, every 12 hours, they can wait until they return home.<ref name="Lancet_review"/><ref name=cullins/>

Boiling menstrual cups once a month can also be a problem in developing countries, if there is a lack of water, firewood or other fuel.<ref name="APHRC">APHRC (2010). [http://www.susana.org/en/resources/library/details/984 Attitudes towards, and acceptability of, menstrual cups as a method for managing menstruation: Experiences of women and schoolgirls in Nairobi, Kenya] {{Webarchive|url=https://web.archive.org/web/20171014000743/http://www.susana.org/en/resources/library/details/984 |date=14 October 2017 }} - Policy Brief No. 21. The African Population and Health Research Center, Nairobi, Kenya</ref>

===Stain removal===
[[File:Tandenrager.jpg|thumb|Rubbery, elastomer interdental brush]]
Smooth-surfaced cups are easier to clean; moulded text, ridges, bumps, and holes make it a bit more difficult.<ref name=wirecutter/> Some suggest scrubbing out grooves with a [[toothbrush]], rag, or cloth,<ref name=nixitFAQ/> and airholes with an [[interdental brush]].

Stains on any color of the cup can be removed or at least lightened by soaking the cup in diluted [[hydrogen peroxide]],<ref name=wirecutter/> or leaving it out in the sun for a few hours.<ref>{{Cite web |last=Rosas |first=Kim |date=January 6, 2023 |title=Tips for Removing Stains on Your Menstrual Cup or Menstrual Disc |url=https://period.shop/blogs/period-shop-blog/remove-menstrual-cup-stains |archive-url=https://web.archive.org/web/20231203035240/https://period.shop/blogs/period-shop-blog/remove-menstrual-cup-stains |archive-date=December 3, 2023 |access-date=February 26, 2024 |website=Period Shop}}</ref> Some cup makers recommend against the use of hydrogen peroxide.<ref name="path_cleaning_review"/><ref>{{Cite web |date=January 25, 2023 |title=How to Clean a Menstrual Cup Properly |url=https://shopdiva.com/blogs/the-conscious-cycle/how-to-clean-a-menstrual-cup-properly |url-status=live |archive-url=https://web.archive.org/web/20240226172313/https://shopdiva.com/blogs/the-conscious-cycle/how-to-clean-a-menstrual-cup-properly |archive-date=February 26, 2024 |access-date=February 26, 2024 |website=Diva}}</ref><ref>{{Cite web |title=How to Clean a Menstrual Cup (It's Easier Than You'd Think) |url=https://rubycup.com/blogs/articles/how-to-clean-menstrual-cup |url-status=live |archive-url=https://web.archive.org/web/20240226172539/https://rubycup.com/blogs/articles/how-to-clean-menstrual-cup |archive-date=February 26, 2024 |access-date=February 26, 2024 |website=Ruby Cup}}</ref>

Some menstrual cups are sold colorless and translucent, but several brands also offer colored cups.<ref>{{Cite web|last=Parker|first=Erin|date=28 July 2020|title=These Period Cup Reviews Might Convince You to Ditch Pads and Tampons for Good|url=https://www.glamour.com/gallery/best-menstrual-cups|access-date=2021-04-10|website=Glamour|language=en-us|archive-date=10 April 2021|archive-url=https://web.archive.org/web/20210410120402/https://www.glamour.com/gallery/best-menstrual-cups|url-status=live}}</ref> Translucent cups lose their initial appearance faster than colored &ndash; they tend to get yellowish stains with use.<ref name="Lancet_review"/> It can be harder to see whether a dark-coloured cup is clean.<ref name=wirecutter/> The shade of a colored cup may change over time, though stains are often not as obvious on colored cups.

===Storage===
[[File:Diva Cup and the Keeper.jpg|thumb|Two menstrual cups with breathable cotton storage bags, one undyed.]]
Manufacturers typically suggest letting the cup dry out fully and storing it dry in a breathable container, such as the cloth bag usually provided with the cup. Airtight wraps and containers are counterrecommended, especially if the cup is at all damp.<ref name="path_cleaning_review"/>

==Safety==
Menstrual cups are a safe option for managing menstruation, with risks comparable to or lower than alternatives (with the possible exception of the risk of [[intrauterine device]] (IUD) displacement). They are safe in in low-, middle-, and high-income settings.<ref name=Lancet_review/>

Using a menstrual cup does not harm the [[vaginal flora]]. Studies looked at disruptions of the vaginal flora including [[vaginal yeast infection|excessive growth of yeast]], [[Bacterial vaginosis|excessive growth of harmful bacteria]], excessive growth of [[Staphylococcus aureus]], and other microorganisms; subjects using menstrual cups were not more likely to have these common vaginal problems than subjects using other methods, (cloth or disposable pads, or tampons); in some studies, they were less likely.<ref name=Lancet_review/>

Menstrual cups can be used with an [[IUD]], but it isn't clear whether using a menstrual cup increases the risk of IUD expulsion, {{asof|lc=yes|2023}}.<ref name=":2" /> About 6% of all IUD users have an IUD come out unintentionally, most commonly during menstruation. In three studies of expulsion rates in menstrual cup users, the rates were 3.7%, 17.3% and 18.6%. Menstrual cup users differ demographically from the general population of IUD users (for instance, they tend to be younger, and youth independently increases the risk of losing an IUD unintentionally). It has been suggested that when removing a menstrual cup, the user might accidentally pull on the IUD string, or that the suction might pull the IUD out. There is no data on what removal techniques, brands or types of cup might be riskier. Some IUD users have had the strings of their IUD cut quite short as a precaution against accidentally pulling it out while removing a cup.<ref name=":2">{{cite journal |last1=Bowman |first1=Nicola |last2=Thwaites |first2=Annette |title=Menstrual cup and risk of IUD expulsion – a systematic review |journal=Contraception and Reproductive Medicine |date=21 January 2023 |volume=8 |issue=1 |page=15 |doi=10.1186/s40834-022-00203-x |doi-access=free |pmid=36670496 |pmc=9863186 |issn=2055-7426}}</ref> So far there is no data on IUD displacement in people using ring-shaped cups, which do not suction to the cervix in the way bell-shaped cups can.<ref name="PN_IUD">{{cite web |last1=Rosas |first1=Kim |title=Can I Use a Menstrual Cup with an IUD |url=https://periodnirvana.com/iud |website=Period Nirvana |access-date=1 September 2024 |date=24 April 2021}}</ref>

===Rare issues===
The number of menstrual cup users is unknown. This makes it hard to estimate the rate of rarer health problems related to cups. There are few reports, and rare problems are unlikely to turn up in a randomized study.<ref name=Lancet_review/>

Serious difficulty removing the cup, requiring professional assistance, is rare but not unknown. A 2019 review found two cases with bell-shaped silicone cups, and one case with an elaborate older model of diaphragm-like cup called a Gynaeseal. There were also 46 reports with a single brand of disposable ring-shaped plastic cup (of about 100 million cups sold); most were reported to the manufacturer.<ref name=Lancet_review/>

A 2019 review found three cases in which a malpositioned menstrual cup pressed on a [[ureter]], which [[hydronephrosis|blocked the flow of urine from a kidney to the bladder]]; this caused [[renal colic]] (acute pain on the flank and lower back) which went away once the cup was removed. It also found one case of urinary incontinence while using the cup, which cleared up when the cup was removed, and five other urinary complaints.<ref name=Lancet_review/>

Most menstrual cups are made of silicone, and silicone allergies are rare. In 2010, there was one report to the FDA of someone with a silicone allergy who had to have reconstructive surgery to the vagina after using a silicone menstrual cup. There were two reports to the [[FDA]] of allergic reactions to a disposable plastic cup. A 2017 study in [[Dharpur]], [[Gujarat]], using a silicone cup described as ring-shaped and depicted as bell-shaped, collected two reports of rashes and one report of an allergy.<ref name=Lancet_review/>

The 2019 review also found two reports of irritation to the vagina and cervix, neither of which had clinical consequences, and two of severe pain (one on removing a cup for the first time). There were three reports of a vaginal wound from menstrual cup use, but reviewers were not able to review any associated medical records.<ref name=Lancet_review/>

One case report noted the development of [[endometriosis]] and [[adenomyosis]] in one menstrual cup user.<ref name=Lancet_review/><ref>{{cite journal | vauthors = Spechler S, Nieman LK, Premkumar A, Stratton P | title = The Keeper, a menstrual collection device, as a potential cause of endometriosis and adenomyosis | journal = Gynecologic and Obstetric Investigation | volume = 56 | issue = 1 | pages = 35–7 | year = 2003 | pmid = 12867766 | doi = 10.1159/000072329 | s2cid = 2419337 | url = https://zenodo.org/record/1235327 | access-date = 20 June 2019 | archive-date = 20 June 2019 | archive-url = https://web.archive.org/web/20190620193153/https://zenodo.org/record/1235327 | url-status = live }}</ref> Endometriosis affects 10–15% of menstruators.<ref name="pmid29276652">{{cite journal| vauthors=Parasar P, Ozcan P, Terry KL| title=Endometriosis: Epidemiology, Diagnosis and Clinical Management |journal=Curr Obstet Gynecol Rep |year=2017 |volume=6 |issue=1 |pages=34–41 |pmid=29276652 |doi=10.1007/s13669-017-0187-1 |pmc=5737931}}</ref> An online survey on the topic, with nine respondents, found three people who had used a menstrual cup and developed endometriosis.<ref name="assocpharmtox.org" /> The [[U.S. Food and Drug Administration]] made a public statement that there was insufficient evidence of risk.<ref>{{cite web|url=https://www.fda.gov/ohrms/dockets/dailys/03/Nov03/112803/03P-0166-ans0001.pdf|title=Citizen Petition on Menstrual Cups & Endometriosis|last=Lione|first=Armand|website=[[Food and Drug Administration]]|access-date=19 December 2010|archive-date=2 November 2017|archive-url=https://web.archive.org/web/20171102230401/https://www.fda.gov/ohrms/dockets/dailys/03/Nov03/112803/03P-0166-ans0001.pdf}}</ref><ref name=Lancet_review/>

===Toxic shock syndrome===
[[Toxic shock syndrome]] (TSS) is a potentially fatal bacterial illness. A 2019 review found the risk of toxic shock syndrome with menstrual cup use to be low, with five cases identified via their literature search (one with an IUD, one with an [[immunodeficiency]]).<ref name=Van2019/> Data from the United States showed rates of TSS to be lower in people using menstrual cups versus high-absorbency tampons.<ref name=Van2019/> Infection risk is similar or less with menstrual cups compared to pads or tampons.<ref name=Van2019/>

There is an association between TSS and [[tampon]] use, although the exact connection remains unclear.<ref name="FDA">{{Cite web|url = https://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PatientAlerts/ucm070003.htm|title = Tampons and Asbestos, Dioxin, & Toxic Shock Syndrome|date = 13 May 2015|access-date = 8 September 2015|publisher = FDA U.S. Food and Drug Administration, U.S. Department of Health and Human Services|archive-date = 26 January 2017|archive-url = https://web.archive.org/web/20170126215810/http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PatientAlerts/ucm070003.htm}}</ref> TSS associated with menstrual cup use appears to be very rare,<ref name="FLOW">{{cite journal |vauthors=Howard C, Rose CL, Trouton K, Stamm H, Marentette D, Kirkpatrick N, Karalic S, Fernandez R, Paget J |date=June 2011 |title=FLOW (finding lasting options for women): multicentre randomized controlled trial comparing tampons with menstrual cups |journal=Canadian Family Physician |volume=57 |issue=6 |pages=e208-15 |pmc=3114692 |pmid=21673197}}</ref><ref>{{cite journal | vauthors = Mitchell MA, Bisch S, Arntfield S, Hosseini-Moghaddam SM | title = A confirmed case of toxic shock syndrome associated with the use of a menstrual cup | journal = The Canadian Journal of Infectious Diseases & Medical Microbiology | volume = 26 | issue = 4 | pages = 218–20 | date = August 2015 | pmid = 26361491 | pmc = 4556184 | doi = 10.1155/2015/560959 | doi-access = free }}</ref> probably because menstrual cups are not absorbent, do not irritate the vaginal [[Mucous membrane|mucosal]] tissue, and so do not measurably change the [[vaginal flora]].<ref name="JWH2011"/>

The risk of TSS associated with contraceptive [[cervical cap]]s <ref>Faculty of Family Planning & Reproductive Health Care (2007). [http://www.fsrh.org/pdfs/archive/CEUGuidanceFemaleBarrierMethodsJune07.pdf Female Barrier Methods.] {{webarchive|url=https://web.archive.org/web/20151126113337/http://www.fsrh.org/pdfs/archive/CEUGuidanceFemaleBarrierMethodsJune07.pdf |date=2015-11-26 }} London: p.3</ref><ref name=Van2019/> and contraceptive diaphragms<ref name=Van2019/> is also very low. Like menstrual cups, these products both use mostly medical grade silicone or latex.<ref name=":16">{{cite journal | vauthors = Juma J, Nyothach E, Laserson KF, Oduor C, Arita L, Ouma C, Oruko K, Omoto J, Mason L, Alexander KT, Fields B, Onyango C, Phillips-Howard PA | title = Examining the safety of menstrual cups among rural primary school girls in western Kenya: observational studies nested in a randomised controlled feasibility study | journal = BMJ Open | volume = 7 | issue = 4 | article-number = e015429 | date = May 2017 | pmid = 28473520 | pmc = 5566618 | doi = 10.1136/bmjopen-2016-015429 }}</ref><ref name=Van2019/>

A widely reported study showed that ''[[in vitro]]'', bacteria associated with toxic shock syndrome (TSS) are capable of growing on menstrual cups,<ref>{{Cite news|url=https://www.consumerreports.org/women-s-health/menstrual-cups-linked-to-toxic-shock-syndrome/|title=Menstrual Cup Linked to Toxic Shock Syndrome, New Study Finds|work=Consumer Reports|access-date=2018-12-03|language=en-US|archive-date=3 December 2018|archive-url=https://web.archive.org/web/20181203202726/https://www.consumerreports.org/women-s-health/menstrual-cups-linked-to-toxic-shock-syndrome/|url-status=live}}</ref><ref>{{Cite news|url=https://www.today.com/health/toxic-shock-syndrome-risks-are-tampons-or-menstrual-cups-safer-t127446|title=Toxic shock syndrome risks: Are tampons or menstrual cups safer?|work=TODAY.com|access-date=2018-12-03|language=en-US|archive-date=4 December 2018|archive-url=https://web.archive.org/web/20181204005652/https://www.today.com/health/toxic-shock-syndrome-risks-are-tampons-or-menstrual-cups-safer-t127446|url-status=live}}</ref><ref>{{cite journal | vauthors = Nonfoux L, Chiaruzzi M, Badiou C, Baude J, Tristan A, Thioulouse J, Muller D, Prigent-Combaret C, Lina G | title = In Vitro | journal = Applied and Environmental Microbiology | volume = 84 | issue = 12 | pages = e00351–18 | date = June 2018 | pmid = 29678918 | pmc = 5981080 | doi = 10.1128/aem.00351-18 }}</ref> but results from similar studies are conflicting, and results from in-vivo studies do not show cause for concern.<ref name=Van2019/>

==Size, shape, and flexibility==
There are no standards for the measurement or size-labelling of menstrual cups, and each manufacturer uses their own system.<ref name=quant_firmness/> Self-measurement of the vagina and third-party measurement tables are often used to get a good fit.<ref name="Anakalia"/><ref name="cervix_height"/><ref name="PNsizechart"/><ref name="thingstoknow"/>

Capacity affects how often the cup must be emptied. Some prefer to empty the cup only twice a day, morning and evening, to avoid emptying it in public toilets.<ref name="Lancet_review"/> Flow rates vary. On average, about 30mL of menstrual fluid is lost per month; 10 to 35mL is normal.<ref name="VHMF">{{cite web |title=Very Heavy Menstrual Flow |url=https://www.cemcor.ubc.ca/resources/very-heavy-menstrual-flow |website=The Centre for Menstrual Cycle and Ovulation Research |publisher=University of British Columbia |language=en |date=30 November 2013 |access-date=16 March 2024 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316171054/https://www.cemcor.ubc.ca/resources/very-heavy-menstrual-flow |url-status=live }}</ref> Menstrual blood loss of more than 80mL per month is considered [[heavy menstrual bleeding]], and grounds for consulting a doctor.<ref name="bloodloss">{{cite journal |last1=O'Brien |first1=SH |title=Evaluation and management of heavy menstrual bleeding in adolescents: the role of the hematologist |journal= Hematology|date=30 November 2018 |volume=2018 |issue=1 |pages=390–398 |doi=10.1182/asheducation-2018.1.390 |pmid=30504337|pmc=6246024 }}</ref><ref>{{cite web |title=Heavy Menstrual Periods |url=https://www.healthlinkbc.ca/illnesses-conditions/sexual-reproductive-health/heavy-menstrual-periods |website=www.healthlinkbc.ca |publisher=HealthLink BC |access-date=16 March 2024 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316172556/https://www.healthlinkbc.ca/illnesses-conditions/sexual-reproductive-health/heavy-menstrual-periods |url-status=live }}</ref><ref name="HMB"/>

The stated capacity of menstrual cup is generally measured ''[[ex vivo]]'' (outside the body). It is the volume of fluid that will fill the cup to just below the airholes, if there are airholes, or just below the rim, if there are none.<ref name="HMB"/> These volume measurements are generally overestimates of [[in-vivo|real life]] capacity, because the cup may be compressed inside the body, and the cervix will often occupy some of the volume of the cup.<ref name=wirecutter/><ref name="Anakalia"/><ref name="invivoMRI"/><ref name="mcr_ziggy"/> ''Ex-vivo'' capacities for menstrual cups are in the range of tens of milliliters;<ref name=UNspec/><ref name="PNsizechart"/> for comparison, a normal-size tampon or pad holds about 5mL when thoroughly soaked.<ref name="VHMF"/>

Smooth cups with no sharp edges are recommended by the UN.<ref name=UNspec/> Moulded text, ridges, bumps, and holes make a cup harder to clean.<ref name="cleaning_test"/><ref name=wirecutter/>

===Bell-shaped cups===
{{Multiple image| align=center| total_width = 800
|image1=Menstrual cups with scale bars 10.1177 17455065211058553-fig2.jpg
|caption1=Bell-shaped menstrual cups come in many different shapes
|alt1=Scale images of 14 different menstrual cups, most bell shaped, two goblet-shaped (a sort of three-quarter-spherical bowl), two with smooth outsides and an asymmetrical thin-membrane turned-in lip, most with cylindrical stems, one with a loop, one with a ladder-like strip of loops, one with no stem.
|image3=Fleurcups sizes.png
|caption3=Most manufacturers make at least two different sizes, sometimes confusingly labelled
|alt3=Two slightly different sizes of very standard cups; the difference is discernable, but not glaring.
|image4=Gestion menstrual copita copa menstrual menstruación periodicas 18.jpg
|alt4=A cup being folded and squished into a cylindrical shape.
|caption4=Softer bell-shaped cups may be more comfortable for some, but firmer cups may have a better seal<ref name=wirecutter/>
|image5=Menstrual cups with scale bars 10.1177 17455065211058553-fig2 (cropped to Fun Cup).jpg
|caption5=A stemless, coloured menstrual cup with an asymmetrical rim to fit a tilted cervix.
|alt5=A blue cup with a pointy but unstemmed tip, the rim cut on a slant, the tip curling a bit towards the side where the rim is short, all rounded as if melted
}}
{| class="wikitable floatright"
|+ UN classification of menstrual cup sizes<ref name=UNspec/>
|-
! Size category !! Length (excluding stem) !! Capacity !! Rim diameter !! Firmness
|-
| Small || 40-50mm || 15-25mL || 36-40mm || soft to medium
|-
| Medium || 45-55mm || 20-30mL || 41-44mm || soft to medium
|-
| Large || 48-58mm || 30-40mL || 45-48mm || medium to hard
|}

Bell-shaped menstrual cups all have a wall thickness of about 2mm. They vary in length, capacity, firmness, and external diameter of the rim. This accommodates variety in anatomy, flow quantity, and personal preferences for firmness.<ref name=UNspec/>

While [[Tenting effect|vaginal tenting]] causes the cervix to retract during sexual arousal, it is normally located within centimeters of the vaginal opening; 45-55mmm is a medium height.<ref name="cervix_height"/> Cups are available in lengths from about 30-80mm,<ref name="PNsizechart"/> with 40-60mm lengths being common;<ref name="Lancet_review"/> most menstrual discs are shallower than most bell-shaped cups.<ref name="disc_fit">{{cite web |last1=Rosas |first1=Kim |title=Menstrual Disc Brands {{!}} Resources and Comparisons |url=https://www.periodnirvana.com/menstrual-disc-brands/ |website=Period Nirvana |access-date=11 March 2024 |date=20 October 2021 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311002325/https://www.periodnirvana.com/menstrual-disc-brands/ |url-status=live }}</ref> Some manufacturers sell several sizes of cup that are all the same length.{{refn|For instance, Aisle Cup, Diva, Genial Day, Keeper, Mermaid Guppy, and Mooncup (UK) all sell several cup sizes that all have the same length; this is not an exhaustive list.<ref name="PNsizechart"/>}}

Cups must be short enough that the cervix does not push the cup into contact with the [[vulva]], where it may be uncomfortable. If the cervix sits particularly low<ref name=UNspec/> or is tilted, a shorter cup may needed.<ref name=":6" /> A cup which is too short may sit too far up to remove easily.<ref name=wirecutter/>

Many bell-shaped cups have stems. The stems can be trimmed to shorten the cup, giving stemmed cups a minimum and maximum length; instructions for trimming are generally included with the cup. Some cups are made in two parts, with a separate stem passing through a hole in the cup; these separate stems, unlike normal one-piece stems, can be pulled to break the seal, and were designed to make removing the cup with low dexterity easier.<ref name="2part">{{cite news |last1=Holt |first1=Willa |title=Health Canada Just Approved Two New Reusable Menstrual Products & 1 Has A Helpful Handle - MTL Blog |url=https://www.mtlblog.com/health-canada-just-approved-two-new-reusable-menstrual-products-1-has-a-helpful-handle |work=www.mtlblog.com |language=en-ca |access-date=16 March 2024 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316184711/https://www.mtlblog.com/health-canada-just-approved-two-new-reusable-menstrual-products-1-has-a-helpful-handle |url-status=live }}</ref> There also exist cups with valves in the stem, which can be slowly drained without removing the cup.<ref name="PN_valve">{{cite web |last1=Rosas |first1=Kim |title=Valve Menstrual cup review |website=Period Nirvana|url=https://www.periodnirvana.com/valve-menstrual-cup-review/https://www.periodnirvana.com/valve-menstrual-cup-review/ |access-date=1 September 2024}}</ref> The UN counterrecommends hollow stems, because solid stems are easier to clean.<ref name=UNspec/>

''[[Ex vivo]]'', small size cups hold about 15-25 ml, medium size cups 20-30 ml, and large cups 30-40 ml.<ref name=UNspec>{{Cite web | title=Menstrual Cup Specifications — General description | url=https://www.unfpa.org/sites/default/files/resource-pdf/Specifications%20Reusable%20Menstrual%20Cup%20%20-%20UNFPA%2C%20UNHCR%2C%20UNICEF.pdf | access-date=February 27, 2023 | website=United Nations Population Fund | archive-date=28 February 2023 | archive-url=https://web.archive.org/web/20230228002614/https://www.unfpa.org/sites/default/files/resource-pdf/Specifications%20Reusable%20Menstrual%20Cup%20%20-%20UNFPA,%20UNHCR,%20UNICEF.pdf | url-status=live }}</ref> The maximum capacity for large cups is about 50mL (ring-shaped cups generally hold a bit more than bell-shaped cups).<ref name="PNsizechart"/>  Excessively high-volume cups can be uncomfortably large, so fit is prioritized.<ref name=wirecutter/>

Bell-shaped cups also vary by firmness or flexibility. Some manufacturers make the same cups in a range of firmness levels. A firmer cup pops open more easily after insertion and may hold a more consistent seal against the vaginal wall (preventing leaks), but some people find softer cups more comfortable to insert.<ref name="Lancet_review">{{Cite journal|last1=Eijk|first1=Anna Maria van|last2=Zulaika|first2=Garazi|last3=Lenchner|first3=Madeline|last4=Mason|first4=Linda|last5=Sivakami|first5=Muthusamy|last6=Nyothach|first6=Elizabeth|last7=Unger|first7=Holger|last8=Laserson|first8=Kayla|last9=Phillips-Howard|first9=Penelope A.|author-link8=Kayla Laserson|date=2019-08-01|title=Menstrual cup use, leakage, acceptability, safety, and availability: a systematic review and meta-analysis|journal=The Lancet Public Health|language=en|volume=4|issue=8|pages=e376–e393|doi=10.1016/S2468-2667(19)30111-2|issn=2468-2667|pmid=31324419|pmc=6669309|doi-access=free}}</ref> The outside diameter of the rim will also affect seal and comfort.{{citation needed|date=March 2024}}

====Sizing====
Cervix height is measured by touching the cervix with a fingertip, and using the thumb against the finger to mark the inner edge of the vaginal opening; the distance from the thumbnail to the tip of the finger is the height of the cervix.<ref name="cervix_height">{{cite web |last1=Rosas |first1=Kim |title=High vs. Low Cervix and Menstrual Cups |url=https://www.periodnirvana.com/why-measuring-your-cervix-height-matters-low-cervix-or-high-cervix-menstrual-cups/ |website=Period Nirvana |access-date=10 March 2024 |date=31 August 2022 |archive-date=24 May 2024 |archive-url=https://web.archive.org/web/20240524203709/https://www.periodnirvana.com/why-measuring-your-cervix-height-matters-low-cervix-or-high-cervix-menstrual-cups/ |url-status=live }}</ref> Cervix height varies slightly over the month, and is usually lowest on the first day of bleeding; minimum height is used for sizing menstrual cups.<ref name="cervix_height"/> The cup length is generally taken to be equivalent to the cervix height, but as the cup rim will generally sit in the fornix, some may comfortably take a cup slightly longer than their cervical height.<ref name=Anakalia/> Fornix depth varies, but is usually between 1–5&nbsp;cm (0.5-2 inches).<ref name="anthropometry"/>

Manufacturers do not generally print cup dimensions on the box,<!--Lunette actually publish them online,[https://www.lunette.com/pages/size-guide] but most don't--> but there are third-party tables of dimensions online.<ref name="PNsizechart">{{cite web |last1=Rosas |first1=Kim |title=Menstrual Cup Comparison Chart |url=https://periodnirvana.com/menstrual-cup-chart/ |website=Period Nirvana |access-date=11 March 2024 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311002325/https://periodnirvana.com/menstrual-cup-chart/ |url-status=live }}</ref><ref>{{cite web |last1=Hearn |first1=Amanda |title=Menstrual Cup Comparison Chart (Metric) |url=https://putacupinit.com/metricchart |website=Put A Cup In It |access-date=10 March 2024 |date=24 February 2016 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311002349/https://putacupinit.com/metricchart/ |url-status=live }}</ref> This forcers buyers to guess whether a cup will fit. A regulatory requirement for quantitative measurements, including a [[Young's modulus]] measurement of firmness, has been suggested. Research into what measurements would be most useful for selecting a well-sized cup is also needed.<ref name="quant_firmness"/>

Most brands sell a smaller and a larger size, but some sell up to five sizes, and differing firmnesses. Sizes are mostly labelled transparently, (e.g. "S", "M", and "L"), but some manufacturers label sizes with ordinal numbers (e.g. "0", "1", and "2"), alphabetic letters (e.g. "A" "B" and "C"), or euphemisms (such as "Petite", "Regular", and "Full fit"). Between one manufacturer's products, volume ''usually'' increases with number and position in the alphabet.<ref name="thingstoknow"/> Mostly, each larger size is slightly larger in all dimensions, but some manufacturers have sizes that differ in only one dimension (length, diameter, or capacity).{{refn|Libby and Juju cups do not follow the conventional order; Aislecups and Genial Day cups differ in diameter, but not length or volume; Divacups do not differ in length; Keeper and Oi differ in volume only.<ref name="PNsizechart"/>}}

These sizes are not consistent between manufacturers.<ref name="quant_firmness"/><ref name=wirecutter/> Manufacturers typically recommend the smaller size for under-30s who have not given birth vaginally and have a lighter flow, and the larger for everyone else.<ref name=":9" /><ref name=":6">{{Cite web|title=What's a Menstrual Cup?|url=https://www.webmd.com/women/guide/menstrual-cup#2|website=WebMD|language=en|access-date=2020-05-22|archive-date=3 October 2018|archive-url=https://web.archive.org/web/20181003170920/https://www.webmd.com/women/guide/menstrual-cup#2|url-status=live}}</ref> However, there is no medical evidence for sizing based on age or [[Gravidity and parity#Parity|parity]].<ref name=":9">{{Cite book|last=Gunter, Jen|title=The vagina bible: the vulva and the vagina--separating the myth from the medicine|date=20 August 2019| isbn=978-0-7352-7738-0| page=304| publisher=Random House of Canada |oclc=1099676519}}</ref>

=== Ring-shaped cups or discs ===
{{Multiple image| align=center| total_width = 1000
|image1=Менструальный диск и менструальная чаша (cropped to menstrual disk).jpg
|caption1=A reusable silicone menstrual disc or ring. The thin-walled bowl is much more flexible than in a bell-shaped cup. The bowl on this cup is covered with a lattice of ridges on the inside.
|alt1=A menstrual disc/ring, made of silicone, bright pink. The rim has a round cross-section and is about 1cm thick; it forms an oval. The bowl is a crumpled, slightly translucent silicone membrane, with a latticework of slightly raised ridges in the shape of a tesselation of hearts.
|image2=Менструальный диск (вид сбоку) (cropped to disc).jpg
|caption2=Side view of the same item, showing grooved rim and slightly asymmetrical, translucent bowl. Note [[moulding flash]] on rim, showing where the two-part mould joined.
|alt2=The rim steps smoothly from one height on one end to a somewhat shorter height on the other. On the end with the taller rimm, the bowl becomes a bit shallower. The outside of the bowl is smooth, but the lattice can be seen through it. There is a small 3-by-9 rectangle of raised dots out the outside to show where to pinch, and a very visible moulding flash.
|image3=Diaphragmen in verschiedenen Größen (cropped).jpg
|alt3=A stack of five roughly hemispherical diaphragms, each with a circular rim which is round in cross-section, all circularly symmetric. Next to them, a single diaphragm in a different colour; one portion of the near-circular rim bulges slightly, and the bowl near it has a deep, narrow moulded-in dimple, concave on the side that the main bowl is convex. The bowls are quite thin silicone rubber, a membrane that crumples under slight pressure; but the rims are more than a centimeter thick and hold their shape.
|caption3=Contraceptive diaphragms; one arced-rim diaphragm intended to fit sizes 65-80mm, and five in 5mm-increment diameters from 60-90mm.<ref>{{cite web |title=Das neue Singa Diaphragma – Medintim |url=https://www.medintim.de/de/news/singa-diaphragma/ |website=www.medintim.de |access-date=11 March 2024 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311034118/https://www.medintim.de/de/news/singa-diaphragma/ |url-status=live }}</ref> These are shaped similarly to menstrual discs, but they are [[overmoulded]], silicone with a springy nylon core in the rim.<ref name=path/>
|image4=Contraceptive Diaphragm side view.jpg
|caption4=A side view of the same arced-rim diaphragm as in the previous picture. The bumps on the rim indicate where to pinch the rim in order to compress the device for insertion. The indentation near the hand is intended to aid removal. The S-shaped profile of the rim (as seen from the side) is intended to let the cup squish to fit a broader range of sizes.<ref name=path/>
|alt4=The rim is strongly concave on the same side that the main bowl is concave. The cup is bilaterally symmetric.
}}

Ring-shaped cups (also called menstrual discs or rings)<ref name="Van2019" /> are often approximately hemispherical in shape, like a [[Diaphragm (birth control)|diaphragm]], with a flexible ring rim and a soft, collapsible center. They collect menstrual fluid like menstrual cups, but sit in the [[vaginal fornix]] and stay in place by hooking behind the [[Pubis (bone)|pubic bone]]. Menstrual discs come in both disposable and reusable varieties.<ref>{{Cite journal |last=Koskenniemi |first=Aino |date=2023-01-02 |title=Say no to shame, waste, inequality—and leaks! Menstrual activism in the market for alternative period products |url=https://www.tandfonline.com/doi/full/10.1080/14680777.2021.1948885 |journal=Feminist Media Studies |language=en |volume=23 |issue=1 |pages=19–36 |doi=10.1080/14680777.2021.1948885 |s2cid=237756421 |issn=1468-0777 |hdl=10138/357657 |hdl-access=free |access-date=23 May 2023 |archive-date=13 August 2023 |archive-url=https://web.archive.org/web/20230813110332/https://www.tandfonline.com/doi/full/10.1080/14680777.2021.1948885 |url-status=live }}</ref>

Ring-shaped cups are sized differently than bell-shaped cups. Fit is much less individual; the flexible bowl makes depth unimportant, and any ring-shaped cup between 60-70mm diameter will fit most people adequately.<ref>{{cite web |last1=Rosas |first1=Kim |title=Menstrual Disc Brands: Resources and Comparisons |url=https://www.periodnirvana.com/menstrual-disc-brands/ |website=Period Nirvana |date=20 October 2021 |access-date=11 March 2024 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311002325/https://www.periodnirvana.com/menstrual-disc-brands/ |url-status=live }}</ref>{{better source needed|COI|date=March 2024}} Sizing is measured in the same way as it is for contraceptive diaphragms, which fit in the same position.<ref name="discsize">{{cite web |last1=Rosas |first1=Kim |title=How to Find Your Menstrual Disc Size |url=https://www.periodnirvana.com/find-your-menstrual-disc-size/ |website=Period Nirvana |date=13 April 2022 |access-date=26 February 2024 |archive-date=26 February 2024 |archive-url=https://web.archive.org/web/20240226023823/https://www.periodnirvana.com/find-your-menstrual-disc-size/ |url-status=live }}</ref>

A study of circular-rim diaphragms failed to find any [[proxy measurement|proxy]] factor (like parity or weight) which would allow prediction of the size of diaphragm someone needed; it was necessary to take a measurement.<ref name="diaphragm_sizes">{{cite journal |last1=Mauck |first1=C |last2=Lai |first2=JJ |last3=Schwartz |first3=J |last4=Weiner |first4=DH |title=Diaphragms in clinical trials: is clinician fitting necessary? |journal=Contraception |date=April 2004 |volume=69 |issue=4 |pages=263–6 |doi=10.1016/j.contraception.2003.11.006 |pmid=15033398 |url=https://www.contraceptionjournal.org/article/S0010-7824(03)00302-0/abstract |access-date=16 March 2024 |archive-date=13 March 2024 |archive-url=https://web.archive.org/web/20240313203043/https://www.contraceptionjournal.org/article/S0010-7824(03)00302-0/abstract |url-status=live |url-access=subscription }}</ref> As with contraceptive diaphragms, some "one-size-fits-all" cups have slightly oval or pear-shaped rims, and some have rims that arch (as seen from the side), increasing the range of sizes that fit. A contraceptive diaphragm using these techniques was found to fit 98% of volunteers in a multicenter study (everyone with a size of 65-80mm).<ref>{{cite journal | title = Contraceptive Efficacy, Safety, Fit, and Acceptability of a Single-Size Diaphragm Developed with End-User Input | journal = Obstetrics and Gynecology | doi = 10.1097/AOG.0000000000000721 | pmid = 25751199 | volume = 125 | issue = 4 | year = 2015 | pages = 895–903 | last1 = Schwartz | first1 = Jill L. | last2 = Weiner | first2 = Debra H. | last3 = Jou Lai | first3 = Jaim | last4 = Frezieres | first4 = Ron G. | last5 = Creinin | first5 = Mitchell D. | last6 = Archer | first6 = David F. | last7 = Bradley | first7 = Lynn | last8 = Barnhart | first8 = Kurt T. | last9 = Poindexter | first9 = Alfred | last10 = Kilbourne-Brook | first10 = Maggie | last11 = Callahan | first11 = Marianne M. | last12 = Mauck | first12 = Christine K. | s2cid = 205466445 | url = http://www.escholarship.org/uc/item/65q612hq | access-date = 11 March 2024 | archive-date = 11 March 2024 | archive-url = https://web.archive.org/web/20240311034120/https://escholarship.org/uc/item/65q612hq | url-status = live }}</ref><ref name="path">{{cite web |last1=Kilbourne-Brook |first1=Maggie |last2=Hammack |first2=Rachel |title=Reinventing the Past to Reshape the Future of Contraception: THE STORY OF THE SILCS DIAPHRAGM |url=https://www.caya.us.com/wp-content/uploads/2022/06/The-Story-of-the-SILCS-Diaphragm.pdf |publisher=PATH |access-date=12 March 2024 |archive-date=12 March 2024 |archive-url=https://web.archive.org/web/20240312033708/https://www.caya.us.com/wp-content/uploads/2022/06/The-Story-of-the-SILCS-Diaphragm.pdf |url-status=live }}</ref> A disc which is too big or too small will leak.<ref name="discsize"/>

Ring-shaped cups come in diameters from 53mm to 80mm, {{As of|lc=y|2024}}.<ref name="PNsizechart"/> They have some advantages over bell-shaped cups, including that they have a higher ''[[ex-vivo]]'' capacity (40-80ml),<ref>{{Cite journal |last1=DeLoughery |first1=Emma |last2=Colwill |first2=Alyssa |last3=Edelman |first3=Alison |last4=Samuelson Bannow |first4=Bethany |date=January 9, 2024 |title=Red blood cell capacity of modern menstrual products: considerations for assessing heavy menstrual bleeding |url=https://srh.bmj.com/content/50/1/21 |journal=BMJ Sexual & Reproductive Health |volume=50 |issue=1 |pages=21–26 |doi=10.1136/bmjsrh-2023-201895 |pmid=37550075 |pmc=10847380 |via=BMJ Journals |access-date=26 February 2024 |archive-date=26 February 2024 |archive-url=https://web.archive.org/web/20240226034811/https://srh.bmj.com/content/50/1/21 |url-status=live }}</ref> enable bloodless period sex,<ref>{{Cite web |last=Loreto Cruz |first=Anne |date=January 19, 2021 |title=Everything you need to know about menstrual discs |url=https://mashable.com/article/menstrual-discs-explainer |url-status=live |archive-url=https://web.archive.org/web/20240226025049/https://mashable.com/article/menstrual-discs-explainer |archive-date=February 26, 2024 |access-date=February 24, 2024 |website=Mashable}}</ref> and are more comfortable for some users.<ref name=":1" /><ref name=":10">{{Cite journal |last1=Abigail |first1=Liberty |last2=Bethany |first2=Samuelson Bannow |last3=Matteson |first3=Kristen |last4=Edelman |first4=Alison |last5=Colwill |first5=Alyssa |date=February 15, 2023 |title=Menstrual Technology Innovations and the Implications for Heavy Menstrual Bleeding |journal=Obstetrics & Gynecology |volume=141 |issue=4 |pages=666–673 |doi=10.1097/AOG.0000000000005126 |pmid=36791417 |pmc=10026971 }}</ref> Disadvantages include messier removal<ref name=":10" /> and more difficulty learning to insert them than for bell-shaped cups.<ref name="thingstoknow"/>

Some ring-shaped cups have removal aids. These may be stringlike stems, notches (dents in the outside of the bowl), and pull loops (like the [[Drink_can#Opening_mechanisms|ring-pull tab]] of a drinks can, or like a strap running parallel to the rim), and some have hybrid looped notches (with a strap across the rim of the notch). Notched or looped disks may rotate in the body so that the grip is out of reach, so some cups have three notches/loops spaced around the circumference of the cup.<ref name=pn_disc_removal/><ref name="PN_formoonsa_review">{{cite web |last1=Rosas |first1=Kim |title=Formoonsa Disc Review {{!}} Taiwan's First Reusable Menstrual Disc |url=https://www.periodnirvana.com/formoonsa-disc-review/ |website=Period Nirvana |access-date=1 September 2024 |date=8 March 2023}}</ref> Notches reduce cup volume.<ref name="PN_saalt_disc_review">{{cite web |last1=Rosas |first1=Kim |title=Saalt Disc Review {{!}} Features and Comparisons |url=https://www.periodnirvana.com/saalt-disc-review/ |website=Period Nirvana |access-date=1 September 2024 |date=27 January 2022}}</ref> Removal aids like pull loops make ring-shaped cups easier to remove without spilling, but they may chafe,<ref name="PN_divadisc_review"/> and can be harder to clean.

Some menstrual rings have ribbed membranes. It is difficult to mould thin membranes; the silicone or plastic has to flow into a very narrow part of the mould, and solidify only once it has filled the area. While it is possible to mould silicone membranes as thin as a quarter of a millimeter thick ({{convert|0.25|cm|inch|disp=out|1}}), it requires care.<ref>{{cite web |title=Liquid Silicone Rubber (LSR) Molding {{!}} Design Guidelines |url=https://www.protolabs.com/services/injection-molding/liquid-silicone-rubber-molding/design-guidelines/ |website=www.protolabs.com |access-date=31 August 2024 |archive-date=31 August 2024 |archive-url=https://web.archive.org/web/20240831235945/https://www.protolabs.com/services/injection-molding/liquid-silicone-rubber-molding/design-guidelines/ |url-status=live }}</ref> Adding ribs (linear thicker areas) to the membrane makes it easier to mould. It also stiffens the membrane.<ref>{{cite web |last1=Technologies |first1=SyBridge |title=Thin Wall Injection Molding Design Tips and Tricks |url=https://sybridge.com/thin-wall-injection-molding-design-tips-and-tricks/ |website=SyBridge Technologies |access-date=31 August 2024 |date=2 August 2022 |archive-date=1 September 2024 |archive-url=https://web.archive.org/web/20240901000045/https://sybridge.com/thin-wall-injection-molding-design-tips-and-tricks/ |url-status=live }}</ref> Stiffer membranes may be more noticeable during sex, and smoother, softer ones less noticeable.<ref name="wh_zf"/><ref name="PN_nixit_review">{{cite web |last1=Rosas |first1=Kim |title=nixit Cup Review {{!}} A Reusable Alternative |url=https://www.periodnirvana.com/nixit-cup-review/ |website=Period Nirvana |access-date=1 September 2024 |date=23 July 2021}}</ref> It is anecdotally claimed that the increase in surface area from the ridges allows ridged cups to hold more blood; and that they may reduce effective natural [[vaginal lubrication]] when worn during sex.<ref name="wh_zf">{{cite news |last1=Lampen |first1=Claire |title='I Had Period Sex Wearing Two Different Menstrual Cups' |url=https://www.womenshealthmag.com/sex-and-love/a20729182/best-menstrual-cup-for-sex-ziggy-flex/ |access-date=31 August 2024 |work=Women's Health |date=24 May 2018 |archive-date=31 August 2024 |archive-url=https://web.archive.org/web/20240831235945/https://www.womenshealthmag.com/sex-and-love/a20729182/best-menstrual-cup-for-sex-ziggy-flex/ |url-status=live }}</ref> Texture may also be added to the outside of the membrane for grip,<ref name="PN_formoonsa_review"/> although it is usually the rim that is gripped when removing the cup.<ref name=pn_disc_removal/>

Rings with a slimmer rim can be easier to slide around the cervix.<ref name="PN_disc_body">{{cite web |last1=Rosas |first1=Kim |title=Is it Your Body or The Fit? 3 Reasons Menstrual Discs Won't Work For You |url=https://www.periodnirvana.com/reasons-menstrual-discs-wont-work/ |website=Period Nirvana |access-date=1 September 2024 |date=5 June 2024}}</ref> A thin spot in the rim can let the rim fold more tightly for insertion and removal.<ref name="PN_flex_reusable_review">{{cite web |last1=Rosas |first1=Kim |title=Flex Reusable Menstrual Disc Review |url=https://www.periodnirvana.com/flex-disc-reusable-review/ |website=Period Nirvana |access-date=1 September 2024 |date=10 May 2022}}</ref> Some ring-shaped cups also have concentric grooves on the outside of the rim; these can be harder to clean than an ungrooved rim.<ref name=nixitFAQ/> Grooves add stiffness while using less material; see [[I-beam]].

Firmer ring-shaped cups can be easier to get into place, as they are stiffer, but softer rings fold more easily and tightly, and may be more comfortable to insert and remove. Firmer disks are therefore often preferred by new users. Unlike in bell-shaped cups, firmness does not affect the seal of a properly-fitting ring-shaped cup.<ref name="PN_disc_firmness">{{cite web |last1=Rosas |first1=Kim |title=When Menstrual Disc Firmness Matters |url=https://www.periodnirvana.com/menstrual-disc-firmness/ |website=Period Nirvana |date=17 March 2022 |access-date=20 March 2024 |archive-date=20 March 2024 |archive-url=https://web.archive.org/web/20240320190228/https://www.periodnirvana.com/menstrual-disc-firmness/ |url-status=live }}</ref><ref name="disc_fit"/>

As more women seek comfort and sustainability in period care, menstrual discs are rapidly emerging as a popular choice. According to a study published in ''BMC Women's Health'', 37% of participants reported using reusable menstrual products during their last period, signalling a strong shift towards eco-friendly alternatives. Among these, menstrual discs stand out for their comfort, adaptability, and leak-proof protection.<ref>{{Cite web |last=mimi |first=my |title=are menstrual discs the period product we've been waiting for? |url=https://mymimi.com.au/pages/are-menstrual-discs-the-period-product-weve-been-waiting-for |access-date=2025-01-28 |website=my mimi |language=en}}</ref> 

==== Sizing ====
Size can be measured in the same way as for contraceptive diaphragms;<ref name="discsize"/> the fore and middle fingers are inserted until the tip of the middle finger is in the [[posterior fornix]] (the hollow on the spinewards side of the cervix), and the thumb is used against the forefinger to mark where the bony [[pubic arch]] touches the index finger. The diagonal distance between the tip of the middle finger and the thumbnail is then measured. This is the diameter of circular rim needed.<ref name="discfit">{{cite journal |last1=Allen |first1=RE |title=Diaphragm fitting. |journal=American Family Physician |date=1 January 2004 |volume=69 |issue=1 |pages=97–100 |pmid=14727824 |url=https://www.aafp.org/pubs/afp/issues/2004/0101/p97.html |access-date=11 March 2024 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311024244/https://www.aafp.org/pubs/afp/issues/2004/0101/p97.html |url-status=live }}</ref> At this depth the side walls of the vagina are quite stretchy,<ref name="anthropometry"/> so no side-to-side measurement is needed.

Sizing rings can also be used. Disposable menstrual discs are also similar in size to many reusable ones, and can be used to check if an ~70mm diameter fits.<ref name="discsize"/><ref name="discfit"/>

Many brands have a one-size-fits-most approach. Some sell two or three sizes, based on qualitative cervix height (low or high) rather than age or previous births.<ref name=wirecutter>{{Cite web |last=Eveleth |first=Rose |date=February 13, 2024 |title=The Best Menstrual Cups and Discs |url=https://www.nytimes.com/wirecutter/reviews/best-menstrual-cup/ |url-status=live |archive-url=https://web.archive.org/web/20240226023455/https://www.nytimes.com/wirecutter/reviews/best-menstrual-cup/ |archive-date=February 26, 2024 |access-date=February 24, 2024 |website=Wirecutter}}</ref><ref>{{Cite web |last=Rosas |first=Kim |date=April 13, 2022 |title=How to Find Your Menstrual Disc Size |url=https://www.periodnirvana.com/find-your-menstrual-disc-size/ |url-status=live |archive-url=https://web.archive.org/web/20240226023823/https://www.periodnirvana.com/find-your-menstrual-disc-size/ |archive-date=February 26, 2024 |access-date=February 25, 2024 |website=Period Nirvana}}</ref> While North American manufacturers do not generally give dimensions, third-party tables of disc diameters are available online.<ref name="PNsizechart"/> European manufacturers generally do give the metric dimensions of their products online.

For circular rims, the outside rim diameter should match the diaphragm size. For oval and slightly egg-shaped rims, the sizing [[Circumference#Ellipse|should be similar]], but taking an average of the [[Semi-major and semi-minor axes|two rim dimensions]].{{citation needed|date=March 2024}} For complex three-dimensional rims, the manufacturer should indicate the size range the cup will fit.

==Materials and color==
Cups are made from rubbers ([[elastomer]]s). Most are made from silicone rubber; some are made from [[latex]] or [[thermoplastic rubber]].<ref name=wirecutter/> Some contain other ingredients, such as colourants<ref name=UNspec/> or cheap bulking fillers.<ref name="Anakalia"/> Cups made from good-quality materials last longer.<ref name=PN_materials/>

A UN specification says that cups must be made of medical-grade silicone.<ref name=UNspec/> There are multiple medical grades.<ref name="casco_silicone">{{cite web |title=Silicone Rubber: What Is Medical Grade Silicone? |url=https://www.cascobaymolding.com/silicone |website=Casco Bay Molding |access-date=30 March 2024 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330010504/https://www.cascobaymolding.com/silicone |url-status=live }}</ref><ref name="casco_wholesale">{{cite web |title=Wholesale Menstrual Cup Production |url=https://www.cascobaymolding.com/wholesale-menstrual-cup |website=Casco Bay Molding |access-date=29 March 2024 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330005631/https://www.cascobaymolding.com/wholesale-menstrual-cup |url-status=live }}</ref> Plastics can also be medical-grade. Some jurisdictions require the use of medical-grade materials, but others do not. Where permitted, cups may be made of cheaper food-grade materials. The same make and model of cup may be made of different materials in different legal jurisdictions.<ref name="USvsRest">{{cite web |title=US Version Cups vs. Rest of the World Cups|url=https://meluna-usa.com/index.php/blog/14-us-version-cups-vs-rest-of-the-world-cups|archive-url=https://web.archive.org/web/20160222091637/https://meluna-usa.com/index.php/blog/14-us-version-cups-vs-rest-of-the-world-cups|date=14 February 2016 |website=Meluna-usa.com |publisher=Meluna USA |archive-date=22 February 2016}}</ref><ref name="diff_materials">{{cite web |last1=Obsi |title=FDA |url=https://menstrualcups.wordpress.com/tag/fda/ |website=Menstrual Cups |access-date=31 August 2024 |language=en |archive-date=8 November 2023 |archive-url=https://web.archive.org/web/20231108134433/https://menstrualcups.wordpress.com/tag/fda/ |url-status=live }}</ref>

In many jurisdictions, menstrual products need not list ingredients. Some places, including some US states, have enacted laws requiring food-style ingredient lists, with the percentage of each ingredient.<ref>{{cite news |title=Federal rules don't require period product ingredients on packaging labels. States are stepping in. {{!}} The Lund Report |url=https://www.thelundreport.org/content/federal-rules-dont-require-period-product-ingredients-packaging-labels-states-are-stepping |access-date=31 August 2024 |work=www.thelundreport.org |archive-date=31 August 2024 |archive-url=https://web.archive.org/web/20240831232730/https://www.thelundreport.org/content/federal-rules-dont-require-period-product-ingredients-packaging-labels-states-are-stepping |url-status=live }}</ref> These laws include menstrual cups,<ref>{{cite news |last1=McConnell |first1=Jamie |title=New York Just Made Menstrual History |url=https://msmagazine.com/2019/07/05/new-york-just-made-menstrual-history/ |access-date=31 August 2024 |work=Ms. Magazine |date=5 July 2019 |archive-date=31 August 2024 |archive-url=https://web.archive.org/web/20240831233322/https://msmagazine.com/2019/07/05/new-york-just-made-menstrual-history/ |url-status=live }}</ref> and have been supported by some cup manufacturers.<ref>{{cite web |last1=Valenti |first1=Lauren |title=Why New York's Period Product Labeling Act Is So Important |url=https://www.vogue.com/article/new-york-menstrual-period-product-labeling-act |website=Vogue |access-date=31 August 2024 |date=14 October 2019}}</ref>

===Base materials===
==== Latex ====
[[File:Menstrual cups with scale bars 10.1177 17455065211058553-fig2 (cropped to "The Keeper" cup).jpg|thumb|A bell-shaped cup made from [[latex]].]]
Early cups were made from latex manufactured from plant sap (usually [[gutta-percha]] or [[indiarubber]]). Latex is biodegradable. [[Latex allergy]] is common; around 4% of the general population worldwide has it, and repeated exposure makes a person more likely to develop it.<ref>{{cite journal |last1=Wu |first1=Miaozong |last2=McIntosh |first2=James |last3=Liu |first3=Jian |title=Current prevalence rate of latex allergy: Why it remains a problem? |journal=Journal of Occupational Health |date=March 20, 2016 |volume=58 |issue=2 |pages=138–144 |pmid=27010091 |doi=10.1539/joh.15-0275-RA |pmc=5356959 }}</ref> Biologically-sourced latex may be brown or amber-coloured (see [[natural rubber]]).

Latex can harden over time.<ref name=PN_materials/>

==== Silicone rubber ====
Most brands use a silicone rubber (also called a silicone elastomer) as the material for their menstrual cups. Silicone is durable and hypoallergenic.<ref name="youngwobost">{{cite web|url=http://www.youngwomenshealth.org/alternative_menstrual.html|title=Alternative Menstrual Products|date=28 March 2013|work=Center for Young Women's Health|publisher=Boston Children's Hospital|access-date=30 March 2013|archive-date=24 May 2014|archive-url=https://web.archive.org/web/20140524095353/http://www.youngwomenshealth.org/alternative_menstrual.html}}</ref><ref name=PN_materials>{{cite web |last1=Rosas |first1=Kim |title=TPE vs. Silicone Menstrual Cups |url=https://www.periodnirvana.com/menstrual-cup-materials-tpe-or-silicone/ |website=Period Nirvana |date=10 February 2024 |access-date=11 March 2024 |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311191743/https://www.periodnirvana.com/menstrual-cup-materials-tpe-or-silicone/ |url-status=live }}</ref> Menstrual cups made from silicone are reusable for up to 10 years.<ref name="Van2019" /> The majority of menstrual cups on the market are reusable, rather than disposable.<ref name=":6"/>

Most brands,<ref name="youngwobost"/> and all reputable ones, state that they use a [[medical-grade silicone]].<ref name="RMC_sizechart">{{cite web |title=Menstrual Cup Size Chart: Period Cup Sizes Comparison Chart |url=https://reusablemenstrualcup.com/menstrual-cup-comparison/chart/ |website=Reusable Menstrual Cups |date=1 February 2021 |access-date=30 March 2024 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330005634/https://reusablemenstrualcup.com/menstrual-cup-comparison/chart/ |url-status=live }}</ref> A UN specification requires medical-grade silicone.<ref name=UNspec/> In most regulation systems, there are multiple subgrades of medical-grade silicones. For instance, in the US, class V and class VI are medical grades.<ref name=Anakalia/> Class VI is  subgrouped into non-implantable (or medical-healthcare grade), shortterm-implantable, and longterm-implantable (with 30 days or more being long-term). Menstrual cups are commonly made of non-implantable medical-grade silicone.<ref name="casco_silicone"/><ref name="casco_wholesale"/> There are not specific grades of silicone rubber for long-term mucous membrane contact.

There are also non-regulatory distinctions. Most cups are made from [[liquid silicone rubber]] (LSR),<ref name="casco_wholesale"/> but some seem to be made from [[high-consistency rubber]] (HCR).<ref name="mcr_ziggy"/> While LSR is indeed liquid, HCR is a putty-like material, which makes for differences in the manufacturing process. The former generally uses platinum catalysts to initiate curing (setting); the latter mostly uses peroxide catalysts.<ref name=gems>{{cite web |title=High Consistency Silicone Rubber (HCR) Molding: A Comprehensive Overview |url=https://gems-mfg.com/high-consistency-silicone-rubber-hcr-molding-a-comprehensive-overview/ |website=GEMS Manufacturing |access-date=30 March 2024 |date=25 November 2023 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330005632/https://gems-mfg.com/high-consistency-silicone-rubber-hcr-molding-a-comprehensive-overview/ |url-status=live }}</ref>

While silicone rubbers, as [[polymer]]s, are inert and hypoallergenic, the corresponding [[monomer]]s are not. Silicone menstrual cups must therefore be fully cured before use.{{citation needed|date=March 2024}} Heat accelerates curing.<ref name=gems/>

Silicone rubbers also come in a range of [[Shore A hardness]]es; a Shore hardness of 10 is gumlike, softer than some sponges and foams (chewing gum is about 20<!--not cited, info copied from [[Shore hardness]] article-->), while 80 is harder than the heel of a shoe.<ref name="simtec">{{cite web |last1=Carchia |first1=Umberto |title=LSR Injection Molding vs. High Consistency Rubber |url=https://www.simtec-silicone.com/blogs/liquid-silicone-rubber-injection-molding-vs-high-consistency-rubber-which-is-right-for-you/ |website=SIMTEC |access-date=30 March 2024 |date=24 October 2021 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330005630/https://www.simtec-silicone.com/blogs/liquid-silicone-rubber-injection-molding-vs-high-consistency-rubber-which-is-right-for-you/ |url-status=live }}</ref> The firmness of a cup will be affected by the firmness of the material, but also its shape and dimensions.

==== Plastic ====
[[File:Instead cup.jpg|thumb|A disposable ring-shaped cup, made of [[Kraton (polymer)|Kraton]],<ref name="New York Daily News">{{Cite news |date=November 11, 1999 |title=You Want Me To Put This Where ?? Readers Weigh In On The Latest Device In Feminine Protection. |url=https://www.nydailynews.com/1999/11/11/you-want-me-to-put-this-where-readers-weigh-in-on-the-latest-device-in-feminine-protection/ |url-status=live |archive-url=https://web.archive.org/web/20240226031409/https://www.nydailynews.com/1999/11/11/you-want-me-to-put-this-where-readers-weigh-in-on-the-latest-device-in-feminine-protection/ |archive-date=February 26, 2024 |access-date=February 24, 2024 |work=New York Daily News}}</ref><ref name=":11" /> "a proprietary blend of soft biocompatible polymer compounds in conformance with the United States Pharmacopoeia XIX Class VI criteria for plastics."<ref name="JWH2011"/>]]

Plastics are also used for menstrual cups. The plastics used are generally [[thermoplastic]]s (plastics that soften when heated, and can therefore be heat-moulded). They are also generally rubbery or elastomeric. The [[thermoplastic elastomers]] used in plastic cups are often unspecified, but are often of some medical grade.

The same brand and model of product may be made with different grades of plastic in different jurisdictions, with medical-grade plastic in jurisdictions that require it, and food-grade plastic in those that don't. This may be reflected in the price.<ref name=USvsRest/>

{{clear}}
===Colourants and other additives===
[[File:Compare cup.jpg|thumb|Many cups are uncoloured, but others contain colourants, usually unspecified, and either food- or medical-grade.]]
The silicone or thermoplastics which most brands of cups are produced are naturally colorless and translucent. Several brands offer colored cups as well as, or instead of the colorless ones. A UN specification says that cups must be made of medical-grade silicone, and may include additives like "elastomer, dye or colorant", but no more than 0.5%. It also requires that the additives are non-toxic, non-carcinogenic, non-mutagenic, and do not cause skin irritation or skin sensitization.<ref name=UNspec/>

Manufacturers generally do not specify what colourants they use, even on request.<ref name=coloursafe>{{cite web |title=Coloured Cups – are they safe? |url=https://menstrualcups.wordpress.com/2011/10/20/coloured-cups-are-they-safe/ |website=Menstrual Cups |access-date=31 August 2024 |language=en |date=20 October 2011 |archive-date=8 November 2023 |archive-url=https://web.archive.org/web/20231108134407/https://menstrualcups.wordpress.com/2011/10/20/coloured-cups-are-they-safe/ |url-status=live }}</ref>

In jurisdictions where cups are classed as medical devices, the colourants generally also have to be medical-grade, and fuse permanently to the raw material so that they cannot leach out. In jurisdictions where menstrual cups are classed as consumer devices, colourants need not be medical-grade.<ref name="USvsRest"/><ref name="diff_materials"/> Some manufacturers use colourants certified for use in plastics intended to come in contact with food, for use in toys, and for use in consumer electronics.<ref name=coloursafe/> In some cases, a broader range of colours are available in jurisdictions where menstrual cups are not classed medical devices, and food-grade dyes can be used.<ref name=USvsRest/> The same brand and model of product may be made with different grades of colourant in different jurisdictions.<ref name=USvsRest/>

Because silicone rubbers are relatively expensive, some dodgier manufacturers mix cheaper fillers into their silicone. These fillers are typically not tested for safety.<ref name="Anakalia"/> Such cups may or may not whiten when stretched only a small amount.<ref name=PN_materials/>

==Manufacturing==
Material must be treated carefully during manufacture to avoid contaminating it. ISO certification is used for silicone manufacturing processes,<ref name="casco_wholesale"/> and is required for regulatory approval in some jurisdictions, like Canada.<ref name=canada_hotspot/>

[[Injection molding of liquid silicone rubber]] is used to make most cups. The setup costs (moulds etc.) are significant, so new designs are generally made in runs of about 4000 or more; production runs of existing designs are generally of about 500 or more at a time.<ref name="casco_wholesale"/>

Larger production runs make for cheaper cups, because there are [[fixed cost|fixed set-up costs]] (it takes money to design a cup, set up a production run, and to clean up afterwards). [[Experience curve effect]]s also reduce costs as more cups are made, including for repeated production runs of the same or similar cups. For example, for an extremely complex [[overmoulding]] of silicone on a shaped nylon spring, used for a contraceptive diaphragm, costs on a production run of 500 in 2010 were $20 US per item, while by 2013, batches of 10,000 and improvements in the manufacturing process had brought the cost down to $5 per item. By 2016, further improvements in manufacturing techniques had reduced the [[Factory second|reject rate]], making the product cheaper.<ref name=path/> See [[#Cost|costs section]], below, for non-manufacturing costs.

Good manufacturing will not show [[Flash (manufacturing)|flash]] or conspicuous mould lines.<ref name=Anakalia/> [[Gate mark]]s from the sprues of the mould may also be visible on some cups.<ref name="sprue">{{cite web |last1=Obsi |title=MeLuna – My Thoughts |url=https://menstrualcups.wordpress.com/2009/07/21/meluna-my-thoughts/ |website=Menstrual Cups |access-date=31 August 2024 |language=en |date=21 July 2009 |archive-date=31 August 2024 |archive-url=https://web.archive.org/web/20240831193420/https://menstrualcups.wordpress.com/2009/07/21/meluna-my-thoughts/ |url-status=live }}</ref>

==Regulation==
Regulation varies by jurisdiction. Some international standards are used in multiple jurisdictions, especially those from the [[International Standards Association]]. Menstrual cup manufacturers seek and advertise ISO 13485 certification.<ref name="casco_silicone"/> [[ISO 13485]] (quality management for the design and manufacturing of medical devices) and [[ISO 10993]] (biocompatibility of medical devices) are both used for menstrual cups.<ref name="stds-benchmarks"/> [[ISO 14024]] is an [[ecolabel]] which may be used by any manufacturer achieving certification to that standard;<!--no cite--> it is also used for some menstrual cups.<ref name="stds-benchmarks"/> While ISO standards are none-binding, specific ISO certifications may be legally required by some jurisdictions.<ref name=canada_hotspot/>

Many manufacturers comply with regulations in multiple jurisdictions. They may vary their products in order to do so, using cheaper materials and methods in jurisdictions where they are allowed.<ref name=USvsRest/>

===Australia===
Australia changed its regulatory environment in 2018, exempting menstrual cups from an obligation to register on the Australian [[Therapeutic Goods Administration]] (TGA). Australia requires certain package labelling.<ref name="Australia">{{cite web |title=Guidance on the regulation of menstrual cups in Australia |url=https://www.tga.gov.au/publication/guidance-regulation-menstrual-cups-australia |publisher=Australian Department of Health |archive-url=https://web.archive.org/web/20210301033320/https://www.tga.gov.au/publication/guidance-regulation-menstrual-cups-australia |access-date=30 March 2024|archive-date=2021-03-01 }}</ref>

===Canada===
Canada regulates menstrual cups (like tampons and other insertables) as Class II medical devices. In Canada this means that they must be licensed by [[Health Canada]] before being advertised, imported, or sold. There are standards for materials and manufacturing facilities; getting accreditation and meeting the requirements can take years. There is also separate strong regulation of sustainability claims. This regulation raises costs for Canadian manufacturers; large manufacturers have made statements approving of the regulatory environment, though they complain about online competition from laxer jurisdictions.<ref name=canada_hotspot>{{cite news |last1=Underwood |first1=Katie |title=How Canada Became a Period Product Hotspot |url=https://canadianbusiness.com/ideas/period-underwear-canada/ |access-date=30 March 2024 |work=Canadian Business – How to Do Business Better |date=18 January 2022}}</ref>

Menstrual cups that meet the regulatory requirements to be sold in the United States may not be able to meet the requirements in Canada.<ref name=canada_hotspot/> This means that some menstrual cups manufactured in Canada are sold in the United States, but not in Canada.<ref name="Bfree cup features"/>

===EU===
The EU does not regulate menstrual cups as medical devices, but categorizes them as "general products",<ref name="reg_compare">{{cite journal |last1=Kwak |first1=JI |last2=Nam |first2=SH |last3=Kim |first3=D |last4=An |first4=YJ |title=Comparative study of feminine hygiene product regulations in Korea, the European Union, and the United States. |journal=Regulatory Toxicology and Pharmacology |date=October 2019 |volume=107 |article-number=104397 |doi=10.1016/j.yrtph.2019.05.022 |pmid=31152857 }}</ref> under the [[General Product Safety Directive]]<ref name="stds-benchmarks"/> (now replaced by the [[General Product Safety Regulation]]<ref>{{cite web |title=General Product Safety Regulation - European Commission |url=https://commission.europa.eu/business-economy-euro/product-safety-and-requirements/product-safety/general-product-safety-regulation_en |website=commission.europa.eu |access-date=30 March 2024 |language=en |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330024835/https://commission.europa.eu/business-economy-euro/product-safety-and-requirements/product-safety/general-product-safety-regulation_en |url-status=live }}</ref>). This means that manufacturers, by selling them, guarantee that they are safe, but do not face more oversight than manufacturers of other consumer products.

Some menstrual cups carry the [[EU Ecolabel]], which requires minimum standards for packaging, pollution, emission reduction, and toxic substances in the finished product.<ref>{{cite web|title=EU Ecolabel for Reusable Menstrual Cups: User Manual|version=1|date=July 2023|author=European Commission|url=https://environment.ec.europa.eu/system/files/2023-09/EU%20Ecolabel%20UM%20RMC_22.09.2023.pdf|access-date=16 April 2024|archive-date=15 April 2024|archive-url=https://web.archive.org/web/20240415035031/https://environment.ec.europa.eu/system/files/2023-09/EU%20Ecolabel%20UM%20RMC_22.09.2023.pdf|url-status=live}}</ref>

The EU has the power to order the removal of unsafe products, including from online shops. Manufacturers inside and outside the EU may voluntarily use the [[CE mark]] on packaging to assert that a product meets EU regulations.<ref name="stds-benchmarks"/>

Some EU manufacturers voluntarily got ISO certifications.<ref>{{cite web |title=Are Menstrual Cups Safe & Effective? Lancet Report Response |url=https://www.mooncup.co.uk/blog/menstrual-cup-safety-the-lancet-report/ |website=Mooncup |access-date=30 March 2024 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330023203/https://www.mooncup.co.uk/blog/menstrual-cup-safety-the-lancet-report/ |url-status=live }}</ref>

===South Korea===
Menstrual cups are categorized as "quasi-drugs" in [[South Korea]].<ref name="reg_compare"/> On the 7th of December 2017, the [[Ministry of Food and Drug Safety]] approved the first menstrual cup for sale in South Korea, after a process involving the submission of data from a three-cycle clinical trial on effectiveness, and screening for ten highly hazardous volatile organic compounds.<ref>{{cite news |last1=Eun-byel |first1=Im |title=Korean retailers allowed to sell menstrual 'cup' |url=https://www.koreaherald.com/view.php?ud=20171208050055 |access-date=30 March 2024 |work=The Korea Herald |date=December 8, 2017 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330022642/https://www.koreaherald.com/view.php?ud=20171208050055 |url-status=live }}</ref><ref>{{cite web |last1=Chu |first1=Marian |title=Menstrual cups approved for 1st time in Korea |url=https://www.koreabiomed.com/news/articleView.html?idxno=2079 |website=KBR |access-date=30 March 2024 |language=en |date=8 December 2017 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330022643/https://www.koreabiomed.com/news/articleView.html?idxno=2079 |url-status=live }}</ref>

===US===
The US regulates menstrual cups as Class II medical devices, but this does not mean the same thing as in Canada. The manufacturers of the silicone, the manufacturer that shapes it into cups, and the vendor, must all be registered with the FDA (using a [[510(k) premarket notification]]<ref name="stds-benchmarks"/> and clearance<ref name=whatmean/>) for a product to be sold legally in the United States. They must submit the required paperwork detailing their manufacturing process and similarity to existing products, and provide contact information.<ref name=Anakalia/> The US regulates the end products, but not the materials.<ref name="stds-benchmarks">{{cite web |last1=Muller |first1=Nancy |title=Standards/benchmarks for menstrual cups |url=https://www.rhsupplies.org/fileadmin/uploads/rhsc/Uploads/Other/Standards_for_menstrual_cups.pdf |publisher=[[Reproductive Health Supplies Coalition]] |access-date=30 March 2024 |archive-date=3 July 2024 |archive-url=https://web.archive.org/web/20240703231333/https://www.rhsupplies.org/fileadmin/uploads/rhsc/Uploads/Other/Standards_for_menstrual_cups.pdf |url-status=live }}</ref> Menstrual cups, unlike tampons, do not require premarket review.<ref name="USingreds">{{cite news |last1=Zurek |first1=Erica |title=Federal rules don't require period product ingredients on packaging labels. States are stepping in. - CBS News |url=https://www.cbsnews.com/news/menstrual-pads-tampons-fda-ingredients-labels/ |work=www.cbsnews.com |date=27 April 2023 |access-date=31 March 2024 |archive-date=31 March 2024 |archive-url=https://web.archive.org/web/20240331040759/https://www.cbsnews.com/news/menstrual-pads-tampons-fda-ingredients-labels/ |url-status=live }}</ref><ref>{{cite web |title=Federal Register |url=https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-884/subpart-F/section-884.5400 |website=unblock.federalregister.gov}}, {{cite web |title=CFR - Code of Federal Regulations Title 21 |url=https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=884.5400 |publisher=Food and Drugs Administration |date=14 March 2024| archive-url=https://web.archive.org/web/20240314191211/https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=884.5400 | archive-date=2024-03-14 }}</ref>{{contradictory inline|reason=probably outdated|date=March 2024}}

Some cups claim to be "FDA approved". The Food and Drug administration does not approve Class II medical devices, only Class III medical devices. Menstrual cups are categorized as class II, not class III, so they cannot be "approved", only "cleared", and these claims are inaccurate.<ref name=Anakalia/><ref name=whatmean>{{cite web |title="FDA Approved" Menstrual Cups - What Does It Really Mean? |url=https://www.theperiod.co/blogs/news/fda-approved-menstrual-cups-what-does-it-really-mean |website=The Period Co. |language=en |access-date=30 March 2024 |archive-date=30 March 2024 |archive-url=https://web.archive.org/web/20240330032959/https://www.theperiod.co/blogs/news/fda-approved-menstrual-cups-what-does-it-really-mean |url-status=live }}</ref><!--has this changed as of 2014?<ref name=whatmean/>-->

The FDA requires certain product labelling on (or in) all packaging.<ref name="stds-benchmarks"/>

==Cost==
The costs for menstrual cups vary widely, from US$0.70 to $47 per cup, with a median cost of $23.35 (based on a 2019 review of 199 brands of menstrual cups available in 99 countries).<ref name="Van2019"/> Regulatory environment can have a strong effect on the price, because compliance may be time-consuming and costly.<ref name=canada_hotspot/> For manufacturing costs, see [[#Manufacturing|manufacturing section]], above.

Reusable menstrual products (including reusable menstrual cups) are more economical than [[disposable product|disposable]] pads or tampons.<ref name="FLOW" /><ref>{{Cite journal |last=Weir |first=Caitlyn |date=April 3, 2015 |title=In The Red: A private economic cost and qualitative analysis of environmental and health implications for five menstrual products |url=http://hdl.handle.net/10222/76546 |access-date=February 29, 2024 |website=Dalhousie University|hdl=10222/76546 }}</ref> The same 2019 review looked at costs across seven countries and found that, over 10 years, a menstrual cup costs $460.25 less than 12 disposable pads per period and $304.25 less than 12 tampons per period.<ref name="Van2019" />

Despite the long-term cost savings, the upfront cost of a menstrual cup is a barrier for some.<ref name=":10" />

==Environmental impact==
[[File:Sanitary bin in women's toilet at White Rose Centre.jpg|thumb|Menstrual cups reduce the frequency with which bins near a toilet need to be emptied.]]
Since they are reusable, menstrual cups help to reduce solid [[waste]].<ref>Bharadwaj S, Patkar A. [http://www.wsp.org/Hygiene-Sanitation-Water-Toolkit/Resources/Readings/Bharadwai-2004-Menstrual.doc Menstrual hygiene and management in developing countries: Taking stock] {{Webarchive|url=https://web.archive.org/web/20151226062708/http://www.wsp.org/Hygiene-Sanitation-Water-Toolkit/Resources/Readings/Bharadwai-2004-Menstrual.doc|date=2015-12-26}}; Junction Social 2004.</ref> Some disposable menstrual pads and plastic tampon applicators can take 25 years to break down in the ocean and can cause a significant environmental impact.<ref>{{cite web|date=2010-04-05|title=The Environmental Impact of Everyday Things|url=http://www.thechicecologist.com/2010/04/the-environmental-impact-of-everyday-things/|access-date=22 August 2014|publisher=The Chic Ecologist|archive-date=2014-08-26|archive-url=https://web.archive.org/web/20140826120816/http://www.thechicecologist.com/2010/04/the-environmental-impact-of-everyday-things/}}</ref> Biodegradable sanitary options are also available,<ref>{{cite journal|last=van Schagen|first=Sarah|date=8 November 2008|title=A review of eco-minded feminine products|url=http://grist.org/article/the-red-vadge-of-courage/|journal=[[Grist (magazine)|Grist]]|access-date=22 August 2014|archive-date=28 October 2014|archive-url=https://web.archive.org/web/20141028211625/http://grist.org/article/the-red-vadge-of-courage/|url-status=live}}</ref> and these decompose in a short period of time, but they must be composted, and not disposed of in a landfill.{{citation needed|date=February 2023}}

When considering a 10-year time period, waste from consistent use of a menstrual cup is only a small fraction of the waste of pads or tampons.<ref name="Van2019"/> For example, if compared with using 12 pads per period, use of a menstrual cup would produce only 0.4% of the [[plastic waste]].<ref name="Van2019"/>

Each year, an estimated 20 billion pads and tampons are discarded in North America. They typically end up in landfills or are incinerated, which can have a great impact on the environment. Most of the pads and tampons are made of cotton and plastic. Plastic takes about 50 or more years and cotton starts degrading after 90 days if it is composted.<ref>{{cite journal|vauthors=Li L, Frey M, Browning KJ|year=2010|title=Biodegradability Study on Cotton and Polyester Fabrics|url=http://www.jeffjournal.org/papers/Volume5/5-4-6Frey.pdf|journal=Journal of Engineered Fibers and Fabrics|volume=5|issue=4|page=155892501000500|article-number=155892501000500406 |doi=10.1177/155892501000500406|s2cid=38815400|doi-access=free|access-date=19 January 2017|archive-date=20 November 2017|archive-url=https://web.archive.org/web/20171120065617/http://www.jeffjournal.org/papers/Volume5/5-4-6Frey.pdf|url-status=live}}</ref>

Given that the menstrual cup is reusable, its use greatly decreases the amount of waste generated from menstrual cycles, as there is no daily waste and the amount of discarded packaging decreases as well. After their life span is over, silicone cups can be burned or sent to a landfill.<ref name=":17">{{Cite web |last=Rosas |first=Kim |date=June 1, 2021 |title=How to Dispose of a Menstrual Cup |url=https://www.periodnirvana.com/how-to-dispose-of-a-menstrual-cup/ |url-status=live |archive-url=https://web.archive.org/web/20240301024800/https://www.periodnirvana.com/how-to-dispose-of-a-menstrual-cup/ |archive-date=March 1, 2024 |access-date=February 29, 2024 |website=Period Nirvana}}</ref> Alternatively, one brand offers a recycling program and some hospitals are able to recycle medical grade silicone, including cups.<ref>{{Cite web |title=DIVA™ Free Recycling Program |url=https://www.terracycle.com/en-CA/brigades/diva-en-ca |url-status=live |archive-url=https://web.archive.org/web/20240301024950/https://www.terracycle.com/en-CA/brigades/diva-en-ca |archive-date=March 1, 2024 |access-date=February 29, 2024 |website=Terracycle}}</ref><ref>{{Cite web |title=How to Recycle Your Old Menstrual Cup |url=https://myecoflow.com/how-recycle-old-menstrual-cup/ |url-status=live |archive-url=https://web.archive.org/web/20240301025006/https://myecoflow.com/how-recycle-old-menstrual-cup/ |archive-date=March 1, 2024 |access-date=February 29, 2024 |website=My Eco Flow|date=9 April 2020 }}</ref> Cups made from [[Thermoplastic elastomer|TPE]] can be recycled in areas that accept [[Resin identification code|#7 plastics]]. Rubber cups are compostable.<ref name=":17" />

Menstrual cups may be emptied into a small hole in the [[soil]] or in [[Compost|compost pile]]s, since menstrual fluid is a valuable [[fertilizer]] for plants and any [[pathogen]]s of [[Sexually transmitted infection|sexually transmitted diseases]] will quickly be destroyed by soil microbes.<ref>{{Cite web|last=CalRecycle|title=Composting Reduces Growers' Concerns About Pathogens|url=http://www.calrecycle.ca.gov/Publications/Documents/Organics%5C44200014.doc|access-date=May 15, 2017|archive-date=February 11, 2017|archive-url=https://web.archive.org/web/20170211034730/http://www.calrecycle.ca.gov/Publications/Documents/Organics/44200014.doc}}</ref>{{medref inline|date=August 2024}} The water used to rinse the cups can be disposed of in the same way. This reduces the amount of [[wastewater]] that needs to be [[Sewage treatment|treated]].{{citation needed|date=February 2023}}

In developing countries, solid waste management is often lacking. Here, menstrual cups have an advantage over disposable pads or tampons as they do not contribute to the solid waste issues in the communities or generate embarrassing refuse that others may see.{{citation needed|date=February 2023}}

== History ==
Menstrual cups may have been inspired by other types of vaginal inserts used throughout history.<ref name="DSpace Angular Universal">{{Cite web |title=DSpace Angular Universal |year=1994 |url=https://dr.lib.iastate.edu/entities/publication/1187d6a0-e447-4177-ad1e-7f29e57cee8f |doi=10.31274/rtd-180813-9822 |last1=Klosterman Kidd |first1=Laura |doi-access=free |access-date=21 December 2022 |archive-date=9 June 2023 |archive-url=https://web.archive.org/web/20230609013321/https://dr.lib.iastate.edu/entities/publication/1187d6a0-e447-4177-ad1e-7f29e57cee8f |url-status=live }}</ref> Vaginal inserts had various purposes from birth control, enabling abortions, to supporting a prolapsed uterus.<ref name="DSpace Angular Universal"/> The first version of what we would now call a menstrual cup was a rubber sack attached to a rubber ring created by S.L. Hockert in 1867, which was patented in the United States.<ref name="DSpace Angular Universal"/> An early version of a bullet-shaped menstrual cup was patented in 1932, by the midwifery group of McGlasson and Perkins.<ref>Goddard, L.J. [https://patents.google.com/patent/US1891761A/en US Patent #1,891,761] {{Webarchive|url=https://web.archive.org/web/20240524022556/https://patents.google.com/patent/US1891761A/en |date=24 May 2024 }} (issued December 1932).</ref> [[Leona Chalmers]] patented the first usable commercial cup in 1937.<ref>{{cite journal|vauthors=North BB, Oldham MJ|date=February 2011|title=Preclinical, clinical, and over-the-counter postmarketing experience with a new vaginal cup: menstrual collection|journal=Journal of Women's Health|volume=20|issue=2|pages=303–11|doi=10.1089/jwh.2009.1929|pmc=3036176|pmid=21194348}}</ref> Other menstrual cups were patented in 1935, 1937, and 1950.<ref>Hagedora, Arthur F. [https://patents.google.com/patent/US1996242 US Patent #1,996,242] {{Webarchive|url=https://web.archive.org/web/20200702183302/https://patents.google.com/patent/US1996242 |date=2 July 2020 }} (issued April 1935).</ref><ref>Chalmers, Leona. [https://patents.google.com/patent/US2089113 US Patent #2,089,113] {{Webarchive|url=https://web.archive.org/web/20231203132220/https://patents.google.com/patent/US2089113 |date=3 December 2023 }} (issued August 1937).</ref><ref>Chalmers, Ileona W. [https://patents.google.com/patent/US2534900 US Patent #2,534,900] (issued December 1950).</ref> The Tassaway brand of menstrual cups was introduced in the 1960s, but it was not a commercial success.<ref name="options">Wysocki, Susan. [http://nurse-practitioners.advanceweb.com/Editorial/Content/Editorial.aspx?CC=182215 "New Options in Menstrual Protection"] {{webarchive|url=https://web.archive.org/web/20090524001435/http://nurse-practitioners.advanceweb.com/Editorial/Content/Editorial.aspx?CC=182215|date=2009-05-24}}. ''Advance for Nurse Practitioners'' (November 1997).</ref> Early menstrual cups were made of rubber.<ref name="mayo">{{cite web | last = Pruthi | first = Sandhya | url = http://www.mayoclinic.com/health/menstrual-cup/AN01770 | title = Menstrual cup: What is it? | website = Mayoclinic.com | date = January 30, 2008 | access-date = 1 February 2009 | archive-date = 6 February 2009 | archive-url = https://web.archive.org/web/20090206175449/http://mayoclinic.com/health/menstrual-cup/AN01770 | url-status = live }}</ref> The first menstrual-cup applicator was mentioned in a 1968 Tassaway patent; there are also 21st-century versions, but they have not been a commercial success, {{as of|lc=y|2024}}.<ref name="applicators">{{cite web |last1=Rosas |first1=Kim |last2=Radomirov |first2=R. |title=Menstrual Cup Applicator Comparisons: CupUp, Pixie & Sunny Cup |url=https://www.periodnirvana.com/menstrual-cup-applicators/ |website=Period Nirvana |access-date=16 March 2024 |date=23 October 2023 |archive-date=16 March 2024 |archive-url=https://web.archive.org/web/20240316192520/https://www.periodnirvana.com/menstrual-cup-applicators/ |url-status=live }}</ref>

No medical research was conducted to ensure that menstrual cups were safe prior to introduction on the market.<ref name="assocpharmtox.org">{{cite web | last1 = Lione | first1 = Armand | last2 = Guidone | first2 = Heather C. | title = The ERC online questionnaire of women who used menstrual cups: summary statement of results and a call for additional research | url = http://www.assocpharmtox.org/pages/CupSummaryStatement.html | website = assocpharmtox.org | publisher = Endometriosis Research Centre, Associated Pharmacologists & Toxicologists (APT) | access-date = 22 August 2014 | archive-date = 21 May 2017 | archive-url = https://web.archive.org/web/20170521135515/http://www.assocpharmtox.org/pages/CupSummaryStatement.html | url-status = live }}</ref> Early research in 1962 evaluated 50 volunteers using a bell-shaped cup. The researchers obtained vaginal smears, gram stains, and basic aerobic cultures of vaginal secretions. Vaginal speculum examination was performed, and pH was measured. No significant changes were noted. This report was the first containing extensive information on the safety and acceptability of a widely used menstrual cup that included both preclinical and clinical testing and over 10 years of post-marketing surveillance.<ref name="JWH2011">{{cite journal | vauthors = North BB, Oldham MJ | title = Preclinical, clinical, and over-the-counter postmarketing experience with a new vaginal cup: menstrual collection | journal = Journal of Women's Health | volume = 20 | issue = 2 | pages = 303–11 | date = February 2011 | pmid = 21194348 | pmc = 3036176 | doi = 10.1089/jwh.2009.1929 }}</ref>

In 1987, another latex rubber menstrual cup, The Keeper, was manufactured in the United States. This proved to be the first commercially viable menstrual cup and it is still available today. The first silicone menstrual cup was the UK-manufactured Mooncup in 2001. Most menstrual cups are now manufactured from medical grade silicone properties.

An early menstrual disc, the Gynaeseal, was developed by Dr John Cattanach in 1989, but never found commercial success.<ref>{{Cite web |title='Gynaeseal diaphragm tampon' family planning device |url=https://collection.powerhouse.com.au/object/356924 |url-status=live |archive-url=https://web.archive.org/web/20240225230039/https://collection.powerhouse.com.au/object/356924 |archive-date=February 25, 2024 |access-date=February 25, 2024 |website=Powerhouse Collection}}</ref><ref name="Van2019" /> In 1997, the Instead Feminine Protection Cup began to be sold across the United States.<ref name=":11">{{Cite news |last=Doheny |first=Kathleen |date=April 16, 1997 |title=Just What Women Need--More Choices in Feminine Protection |url=https://www.latimes.com/archives/la-xpm-1997-04-16-ls-49045-story.html |access-date=February 24, 2024 |work=Los Angeles Times |archive-date=26 February 2024 |archive-url=https://web.archive.org/web/20240226034810/https://www.latimes.com/archives/la-xpm-1997-04-16-ls-49045-story.html |url-status=live }}</ref><ref>{{Cite web |date=November 17, 2020 |title=Period products then & now: 1918 to 2020 |url=https://blog.flexfits.com/period-products-1918-vs-today/ |url-status=live |archive-url=https://web.archive.org/web/20240226031011/https://blog.flexfits.com/period-products-1918-vs-today/ |archive-date=February 26, 2024 |access-date=February 25, 2024 |website=The Fornix}}</ref> Designed by Audrey Contente, the disposable disc was made of [[Kraton (polymer)|Kraton]].<ref name="New York Daily News"/><ref name=":11" /> In 2018, reusable silicone discs were introduced.<ref name=":12">{{Cite web |last=Rosas |first=Kim |date=May 28, 2021 |title=Menstrual Cup History: The 1930s to Present Day |url=https://www.periodnirvana.com/menstrual-cup-history/ |url-status=live |archive-url=https://web.archive.org/web/20240226031838/https://www.periodnirvana.com/menstrual-cup-history/ |archive-date=February 26, 2024 |access-date=February 25, 2024 |website=Period Nirvana}}</ref><ref>{{Cite news |last=Scott |first=Ellen |date=December 12, 2019 |title=I tried the menstrual cup you can wear during sex |url=https://metro.co.uk/2018/03/29/tried-menstrual-cup-can-wear-sex-7424968/ |url-status=live |archive-url=https://web.archive.org/web/20240226031932/https://metro.co.uk/2018/03/29/tried-menstrual-cup-can-wear-sex-7424968/ |archive-date=February 26, 2024 |access-date=February 24, 2024 |work=Metro}}</ref> As of 2021, there were ten brands of discs available for purchase in various markets.<ref name=":12" />

Menstrual cups are becoming more popular worldwide, with many different brands, shapes, and sizes on the market.<ref name="youngwobost"/> Most are reusable, though there is at least one brand of disposable menstrual cups currently manufactured.<ref name="youngwobost" />

Some non-governmental organizations (NGOs) and companies have begun to propose menstrual cups to women in developing countries since about 2010, for example in Kenya and South Africa.<ref>African Population and Health Research Center. [http://www.susana.org/en/resources/library/details/985 Use of Menstrual Cup by Adolescent Girls and Women: Potential Benefits and Key Challenges] {{Webarchive|url=https://web.archive.org/web/20170901233550/http://www.susana.org/en/resources/library/details/985 |date=1 September 2017 }}. In: Policy Brief No. 22. Nairobi: APHRC, 2010.</ref> Menstrual cups are regarded as a low-cost and environmentally friendly alternative to sanitary cloth, expensive disposable pads, or "nothing" &ndash; the reality for many women in developing countries.<ref name="APHRC"/>

[[File:Fleurcup and tampons.jpg|thumb|180px|A large menstrual cup (center) can hold about three times as much liquid as a large tampon.]]

=== Acceptability studies ===
{{expand section|date=August 2024}}
In a randomized controlled feasibility study in rural western Kenya, adolescent primary school girls were provided with menstrual cups or menstrual pads instead of traditional menstrual care items of cloth or tissue.<ref name=":4">{{cite journal | vauthors = Phillips-Howard PA, Nyothach E, Ter Kuile FO, Omoto J, Wang D, Zeh C, Onyango C, Mason L, Alexander KT, Odhiambo FO, Eleveld A, Mohammed A, van Eijk AM, Edwards RT, Vulule J, Faragher B, Laserson KF | title = Menstrual cups and sanitary pads to reduce school attrition, and sexually transmitted and reproductive tract infections: a cluster randomised controlled feasibility study in rural Western Kenya | journal = BMJ Open | volume = 6 | issue = 11 | article-number = e013229 | date = November 2016 | pmid = 27881530 | pmc = 5168542 | doi = 10.1136/bmjopen-2016-013229 |doi-access=free}} [[File:CC-BY icon.svg|50px]] Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License] {{Webarchive|url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/ |date=16 October 2017 }}</ref> Girls provided with menstrual cups had a lower prevalence of [[sexually transmitted infections]] than control groups. Also, the prevalence of [[bacterial vaginosis]] was lower among cup users compared with menstrual pad users or those continuing other usual practice.<ref name=":4" />

==Society and culture==
===Public funding for menstrual cups===

The municipality of Alappuzha in [[Kerala]], [[India]] launched a project in 2019 and gave away 5,000 menstrual cups for free to residents.<ref name=":7">{{Cite news|url=https://www.newindianexpress.com/good-news/2019/jun/18/a-kerala-civic-body-is-distributing-5000-menstrual-cups-for-free-heres-why-1991887.html|title=A Kerala civic body is distributing 5,000 menstrual cups for free; here's why!|last=Bechu|first=S|date=18 June 2019|work=The New India|access-date=8 July 2019|archive-date=1 September 2024|archive-url=https://web.archive.org/web/20240901084532/https://www.newindianexpress.com/good-news/2019/jun/18/a-kerala-civic-body-is-distributing-5000-menstrual-cups-for-free-heres-why-1991887.html|url-status=live}}</ref> The purpose of this was to encourage the use of these cups instead of non-biodegradable menstrual pads to reduce waste production.<ref name=":7" />

In 2022, [[Kumbalangi]], a village in Kerala, became [[India]]'s first sanitary-napkin-free [[Panchayati raj|panchayat]] under a project called "Avalkkayi", which gave away 5,700 menstrual cups for free.<ref>{{cite news | url=https://keralakaumudi.com/en/news/news.php?id=729337&u=kumbalangi-goes-modern-becomes-indias-first-sanitary-napkin-free-panchayat-729337 | title=Kumbalangi goes modern, becomes India's first sanitary napkin free panchayat | newspaper=Keralakaumudi Daily | access-date=15 June 2022 | archive-date=14 July 2022 | archive-url=https://web.archive.org/web/20220714214957/https://keralakaumudi.com/en/news/news.php?id=729337&u=kumbalangi-goes-modern-becomes-indias-first-sanitary-napkin-free-panchayat-729337 | url-status=live | vauthors = Daily K }}</ref>

In 2022, the Spanish government began distributing free menstrual cups through public institutions (such as schools, prisons, and health facilities).<ref>{{cite news |title=Spain's paid menstrual leave and abortion bill |url=https://www.reuters.com/world/europe/spains-paid-menstrual-leave-abortion-bill-2022-05-17/ |access-date=15 April 2024 |work=Reuters |date=May 17, 2022 |first1=Christina |last1=Thykjaer |first2=Belén |last2=Carreño |editor1-first=Janet |editor1-last=Lawrence |archive-date=5 April 2023 |archive-url=https://web.archive.org/web/20230405032111/https://www.reuters.com/world/europe/spains-paid-menstrual-leave-abortion-bill-2022-05-17/ |url-status=live }}</ref>

In March 2024, [[Catalonia]], in [[Spain]], started supplying free menstrual cups as part of the "My period, my rules" initiative. The [[universal health care|universal public healthcare system]] supplied one menstrual cup, one pair of [[period underwear]], and two packages of reusable cloth menstrual pads per person, available through local pharmacies. The program covers 2.5 million people and cost the Catalan government €8.5 million (3.40 euros / {{To USD|3.40|EUR|year=2023}} US dollars per person). The program was undertaken for equity, poverty reduction, taboo reduction, and environmental benefits. It is expected to reduce waste from single-use menstrual hygiene products, which had been 9000 [[ton]]s{{clarify|reason=What sort of ton?|date=April 2024}} per year, according to the Catalan government.<ref name="catalonia">{{cite news |title=Catalonia launches free and reusable period products campaign |url=https://www.euronews.com/health/2024/03/06/catalonia-becomes-the-latest-place-in-europe-to-offer-free-and-reusable-period-products |access-date=15 April 2024 |work=euronews |agency=Associated Press |date=6 March 2024 |language=en |author=Sylvia Hui |archive-date=13 April 2024 |archive-url=https://web.archive.org/web/20240413172726/https://www.euronews.com/health/2024/03/06/catalonia-becomes-the-latest-place-in-europe-to-offer-free-and-reusable-period-products |url-status=live }}</ref><ref name="catalonia_reuters">{{cite news |last1=Garcia |first1=Horaci |last2=Gea |first2=Albert |title=Spain's Catalonia hands out free reusable menstruation products |url=https://www.reuters.com/world/europe/spains-catalonia-hands-out-free-reusable-menstruation-products-2024-03-04/ |access-date=15 April 2024 |work=Reuters |date=March 4, 2024 |archive-date=29 May 2024 |archive-url=https://web.archive.org/web/20240529021313/https://www.reuters.com/world/europe/spains-catalonia-hands-out-free-reusable-menstruation-products-2024-03-04/ |url-status=live }}</ref>

=== Developing countries ===
{{Further|Menstrual hygiene management}}
[[File:Women in Meru, Kenya, examining Menstrual Cups (5926104507).jpg|thumb|Women in Meru, Kenya, examining a menstrual cup.]]
Menstrual cups can be useful as a means of [[menstrual hygiene management]] for people in developing countries where access to affordable sanitary products may be limited.<ref name=":0"/><ref>Tellier M, Hyttel M, Gad M. [http://womena.dk/wp-content/uploads/2015/11/Menstrual-Cups-_-WoMena-_-Uganda-Pilot-Study-Report-Dec-2012-new-version.pdf Assessing acceptability and hygienic safety of menstrual cups as a menstrual management method for vulnerable young women in Uganda] {{Webarchive|url=https://web.archive.org/web/20180401033606/http://womena.dk/wp-content/uploads/2015/11/Menstrual-Cups-_-WoMena-_-Uganda-Pilot-Study-Report-Dec-2012-new-version.pdf |date=1 April 2018 }} Red Cross Society's Life Planning Skills Project, Kampala: WoMena, 2012.</ref> A lack of affordable hygiene products means inadequate, unhygienic alternatives are often used, which can present a serious health risk.<ref>{{Cite web |title=Experiences and problems with menstruation among poor women and schoolgirls in Nairobi, Kenya |url=https://www.susana.org/en/knowledge-hub/resources-and-publications/library/details/983 |access-date=2022-11-18 |website=www.susana.org |archive-date=20 May 2017 |archive-url=https://web.archive.org/web/20170520190311/http://www.susana.org/en/resources/library/details/983 |url-status=live }}</ref><ref>{{Cite web |date=2014-09-26 |title=Kenyan girls could solve sanitary problem with banana-fibre pad |first=Moraa |last=Obiria |location=Nairobi |url=http://www.theguardian.com/global-development/2014/sep/26/kenyan-girls-sanitary-problem-banana-fibre-pad |access-date=2022-11-18 |website=The Guardian |language=en |archive-date=1 September 2024 |archive-url=https://web.archive.org/web/20240901084505/https://www.theguardian.com/global-development/2014/sep/26/kenyan-girls-sanitary-problem-banana-fibre-pad |url-status=live }}</ref> Menstrual cups offer a long-term solution compared to some other menstrual hygiene products because they do not need to be replaced monthly.

=== Cultural aspects ===
{{Further|Culture and menstruation}}
Menstrual hygiene products that need to be inserted into the vagina can be unacceptable for cultural reasons. There are myths that they interfere with [[female reproductive organs]] and that they cause females to "lose their [[virginity]]".<ref name="Crofts" />

There is no evidence that tampon use commonly causes trauma to the hymen. Hymens vary, and septate, cribriform or microperforate hymens, rarer physiological variations, may interfere with tampon use.<ref name=paediatrician/><ref>{{cite journal |last1=Goodyear-Smith |first1=FA |last2=Laidlaw |first2=TM |title=Can tampon use cause hymen changes in girls who have not had sexual intercourse? A review of the literature. |journal=Forensic Science International |date=8 June 1998 |volume=94 |issue=1–2 |pages=147–53 |doi=10.1016/s0379-0738(98)00053-x |pmid=9670493 }}</ref> Some ring-shaped menstrual cups are no bulkier than a tampon when folded as recommended.<ref name="JWH2011"/>

Inserting objects (including penises) into the vagina may or may not affect the [[hymen]].<ref name="couldnt"/> Some cultures wrongly think that the state of the hymen can give [[Virginity test|evidence of virginity]], and wrongly believe that inserting anything into the vagina will "break" the hymen.<ref name="couldnt"/><ref name=paediatrician>{{Cite journal |last1=Moussaoui |first1=Dehlia |last2=Abdulcadir |first2=Jasmine |last3=Yaron |first3=Michal |date=March 2022 |title=Hymen and virginity: What every paediatrician should know |journal=Journal of Paediatrics and Child Health |volume=58 |issue=3 |pages=382–387 |doi=10.1111/jpc.15887 |issn=1034-4810 |pmc=9306936 |pmid=35000235}}</ref> This can discourage youths from using cups.<ref>{{Cite journal |last1=Pokhrel |first1=Diksha |last2=Bhattarai |first2=Sabina |last3=Emgård |first3=Malin |last4=von Schickfus |first4=Michael |last5=Forsberg |first5=Birger C. |last6=Biermann |first6=Olivia |date=2021-01-25 |title=Acceptability and feasibility of using vaginal menstrual cups among schoolgirls in rural Nepal: a qualitative pilot study |journal=Reproductive Health |volume=18 |issue=1 |page=20 |doi=10.1186/s12978-020-01036-0 |issn=1742-4755 |pmc=7831234 |pmid=33487171 |doi-access=free }}</ref><ref>{{Cite journal |last1=Huang |first1=Pin-Tzu |last2=Huang |first2=Jiun-Hau |date=2020-05-01 |title=Menstrual Cup Use Intention and the Moderating Effects of Sexual Orientation and Gender Characteristic Among Female University Students in Taiwan: A Theory-Driven Exploration |journal=Archives of Sexual Behavior |language=en |volume=49 |issue=4 |pages=1355–1366 |doi=10.1007/s10508-019-1412-y |pmid=31432360 |s2cid=254265294 |issn=1573-2800 }}</ref>

Despite common cultural beliefs, the state of a hymen cannot be used to [[virginity test|prove or disprove virginity]]. Penile penetration does not lead to predictable changes to female genital organs; after puberty, hymens are highly elastic and can stretch during penetration without trace of injury. Females with a confirmed history of sexual abuse involving genital penetration may have normal hymens. Young females who say they have had consensual sex mostly show no identifiable changes in the hymen. Hymens rarely [[imperforate hymen|completely cover the vagina]], hymens naturally have irregularities in width, and hymens can heal spontaneously without scarring. Many women do not bleed on having vaginal sex for the first time, hymens may not bleed significantly when torn, and vaginal walls may bleed significantly when torn.<ref name="couldnt">{{cite journal |last1=Mishori |first1=R |last2=Ferdowsian |first2=H |last3=Naimer |first3=K |last4=Volpellier |first4=M |last5=McHale |first5=T |title=The little tissue that couldn't - dispelling myths about the Hymen's role in determining sexual history and assault. |journal=Reproductive Health |date=3 June 2019 |volume=16 |issue=1 |page=74 |doi=10.1186/s12978-019-0731-8 |doi-access=free |pmid=31159818 |pmc=6547601 }}</ref>

There has been one news report of the stem of a bell-shaped cup passing outwards through a small side hole in a [[septate hymen]] (a hymen with more than one opening), causing pain on attempted removal. The woman had the problem diagnosed and the cup removed at a hospital. She had previously used the cup without problems for four years.<ref>{{cite news |last1=Stewart |first1=Heather |title='I wish all women knew this information': Woman says menstrual cup sent her to the ER |url=https://www.dailydot.com/news/are-menstrual-cups-safe/ |work=The Daily Dot |date=19 August 2024}}</ref> Some examine their hymen with a mirror before using a menstrual cup.<ref>{{cite web |last1=Rosas |first1=Kim |title=Can Virgins Use a Menstrual Cup |url=https://www.periodnirvana.com/can-virgins-use-menstrual-cups/ |website=Period Nirvana |access-date=1 September 2024 |date=16 November 2020}}</ref>

== See also ==
*[[Cervical cap]]
*[[Diaphragm (birth control)]]
*[[Menstrual Hygiene Day]]
*[[Period underwear]]

== References ==
{{Reflist}}

{{commons}}

{{menstrual cycle}}

{{DEFAULTSORT:Menstrual Cup}}
[[Category:Feminine hygiene]]
[[Category:Menstrual cycle]]
[[Category:Personal hygiene products]]
[[Category:Vagina]]
[[Category:Cervix]]