Cyclical dydrogesterone in secondary amenorrhea: results of a double-blind, placebo-controlled, randomized study.

Secondary amenorrhea in women with normal estrogen levels increases the risk of endometrial carcinoma. Cyclical dydrogesterone induces regular withdrawal bleeding and effectively protects the endometrium of postmenopausal women receiving estrogens. In order to assess the efficacy of dydrogesterone in inducing regular withdrawal bleeds in premenopausal women with secondary amenorrhea or oligomenorrhea and normal estrogen levels, a double-blind, randomized, placebo-controlled, multicenter study was conducted in 104 women using cyclical dydrogesterone as is used for estrogen replacement therapy.