Abstract: Polycystic ovary syndrome（PCOS） is the most common cause of hyperandrogenic anovulatory infertility，with the incidence of 10% among women of reproductive age. The main manifestations include ovulation，hyperandrogenism and polycystic ovary. Since its clinical manifestations are heterogeneous，the etiology of PCOS is still unclear. Nevertheless，the crucial role of hyperandrogenism in PCOS pathogenesis has been recognized in the world. Recently，scientists paid more attention on the early developmental origin hypothesis and epigenetics. We reviewed the role of androgen in ovarian function and its potential mechanism in PCOS pathogenesis.

Key words: Androgens, Polycystic ovary syndrome, pathogenesis, Fetal therapies, Genetics, medical