Polycystic ovary syndrome (PCOS) is a disorder associated with infertility and subfecundity. There is evidence that both the oocyte and the endometrium have abnormalities that contribute to these disorders. These reproductive abnormalities include anovulation, increased early pregnancy wastage, and probable increased risk for a number of pregnancy complications including gestational diabetes and hypertensive disorders of pregnancy, such as pre-eclampsia. Ovulation induction holds the additional iatrogenic risks of multiple pregnancy and ovarian hyperstimulation syndrome. Gonadotropins and gonadotropin agonist therapies should be used with caution in this group of patients. There is emerging evidence that insulin-sensitizing therapy provides benefit for a wide variety of these reproductive abnormalities. In the long term, women with PCOS have multiple risk factors for the development of endometrial cancer, including centripetal obesity, hyperinsulinemia, diabetes, and chronic anovulation, although the association between PCOS and this cancer is less well established in the epidemiological literature. There is little evidence to date that insulin-sensitizing therapies protect against the development of endometrial hyperplasia and cancer.
