Women with PCOS experience insulin resistance—the inability of the body to respond to and use insulin correctly. A chain reaction can result, upsetting hormone balances, causing the ovaries to overproduce male hormones such as testosterone, and disrupting normal ovulation. The first symptom is usually menstrual irregularities—long, irregular, or skipped periods. Other symptoms include excess facial hair (as well as extra hair on the chest, lower abdomen, or thighs), and acne and skin discoloration. What causes it? The condition may be partly inherited, since it tends to run in families.