Polycystic ovarian syndrome (PCOS), also known as Stein-Leventhal syndrome, is a hormonal disorder that affects women of reproductive age. Other synonyms for PCOS include ovarian hyperandrogenism, hyperandrogenic chronic anovulation, sclerocystic ovary syndrome, ovarian dysfunction syndrome, and polycystic ovary disease. These terms all describe the presence of multiple cystic follicles within the ovaries, as well as hormonal imbalances that can lead to irregular periods, acne, weight gain, and other symptoms. While PCOS is a common condition, affecting up to 10% of women, there is no known cure. Treatment options include hormonal contraceptives, insulin-sensitizing medications, and lifestyle changes such as diet and exercise.