Polycystic Ovary Syndrome

What Is It?

Estrogen and progesterone are the female hormones produced by the ovaries. The levels of these hormones vary during the monthly menstrual cycle. They are essential to the development of follicles, which are fluid-filled pockets, containing an egg that is released each month.

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.