Despite sporadic ovarian follicle development, hormonal contraception consistently and uniformly prevents steroidogenesis and ovulation. For their suppressive activity on ovarian androgen production, oral contraceptives remain the treatment of choice for acne and hirsutism in most hyperandrogenic women. Inhibition of the synthesis of endometrial estrogen receptors explains the effectiveness of hormonal contraception in the therapy of dysfunctional uterine bleeding and in the treatment of pain associated with pelvic endometriosis. Through the inhibition of ovarian cyclicity, the contraceptive pill lowers the incidence of functional ovarian cysts, benign breast disease, dysmenorrhea and premenstrual syndrome and shows a consistent and long-lasting protection against ovarian and endometrial cancer.