Polycystic Ovary Syndrome

What Is It?

Estrogen and progesterone are the female hormones produced by the ovaries. These hormones cause monthly menstrual cycles to occur. These hormones also help eggs to develop in follicles, which are fluid-filled pockets, before an egg is released each month to travel down the fallopian tube.

A third hormone, testosterone, also is produced by the ovaries in small amounts. Testosterone is in a broad class of hormones called androgens, and it is the dominant sex hormone in men. Between 4% and 7% of women produce too much testosterone in their ovaries. These women have a pattern of symptoms called polycystic ovary syndrome.

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