The National Institutes of Health (NIH) list polycystic ovary syndrome (PCOS) as a condition in which there is an imbalance of a woman's female sex hormones. This imbalance may cause menstrual cycle and skin changes, small ovarian cysts, trouble getting pregnant and other problems.
WomensHealth.gov reports PCOS is the most common cause of female infertility and as many as five million women in the United States may be affected with the condition. It typically affects women during the teenage or childbearing years.
Ovaries are responsible for producing hormones to regulate the menstrual cycle and ovulation. These include estrogen, progesterone and androgens (sometimes referred to as male hormones).
According to WomensHealth.gov, in women with PCOS, the ovary doesn't produce all of the hormones it needs for an egg to fully mature. The follicles may start growing and building up fluid but ovulation doesn’t occur.
Instead, some follicles may remain as cysts. For these reasons, ovulation doesn’t occur and progesterone isn’t made. Without progesterone, menstrual cycles are irregular or absent.
KidsHealth.org adds with PCOS, ovaries produce higher than normal amounts of androgens which can interfere with egg development and release.
Right now, the cause of PCOS is unknown. But most experts believe several factors could play a role including genetics. Women with PCOS are more likely to have a family member with it. Another could be excess insulin.
KidsHealth.org reports research suggests women with PCOS may produce too much insulin, which signals their ovaries to release extra male hormones.
WomensHealth.gov lists some PCOS symptoms as infrequent, absent, and/or irregular menstrual periods; ovarian cysts; oily skin, dandruff; weight gain or obesity; skin tags; pelvic pain; anxiety or depression; and sleep apnea.
NIH goes on to say the development of male sex characteristics such as decreased breast size, deepening of the voice, clitoris enlargement; increased body hair on the chest, abdomen, face and around the nipples; and male-pattern baldness.