Mechanism and management of ovulatory failure in women with polycystic ovary syndrome.

Polycystic ovary syndrome is the most important cause of chronic anovulation. In women who fail to respond to clomiphene, low-dose FSH given in a step-wise fashion can induce normal follicular growth and ovulation. The failure of the action of endogenous FSH in these women may be related to reduced biological activity of circulating FSH, but may also involve inhibition of its action at follicular level by polypeptide growth factors such as EGF.