The Basics

Polycystic ovary syndrome (PCOS) is caused by hormonal imbalances that curtail or prevent ovulation—the body’s process of producing and releasing eggs from the ovary. Essentially, women with PCOS have an inappropriate production of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) that results in limited egg development and an increase in testosterone and other typically male hormones (androgens). Women with PCOS also have abnormal insulin metabolism, which worsens with anovulation (no ovulation), increases androgens, and leads to obesity.

SYMPTOMS OF PCOS

The hormonal imbalances experienced by women with PCOS can cause the following symptoms:

• Irregular menstrual cycles—those that are 3 to 5 days shorter or longer than a typical cycle (a normal cycle ranges between 21 and 35 days)
• Heavy or absent periods—some women with PCOS only menstruate one to two times a year
• Acne
• Excess facial and body hair

CAUSES OF PCOS

The cause of PCOS is not completely understood. It is clear that there is a genetic basis to the condition, as a woman is more likely to develop the condition if her mother or sister has it. It is also known that disrupted signaling from the brain to the ovary affects ovarian hormone production, which further exacerbates, or worsens, the condition.