English: This graphic displays the changes in ovarian hormones throughout the human lifespan. During childhood, hormone levels are low. During puberty, estrogen begins to fluctuate, followed by progesterone when you first begin ovulating. After 6-12 years the menstrual cycle normalizes into a rhythm during the menstrual years, barring any reproductive health issues or pregnancy and breastfeeding, which pauses the cycling. Perimenopause, similar to puberty, has high fluctuations of estrogen as progesterone slowly begins to decline. Eventually, you stop ovulating, reach menopause, and hormones return to childlike levels with low progesterone. You still need estrogen during menopause to maintain health, and your body makes it through a process called intracrinology.