A progestin that promotes differentiation and maintenance of the endometrium, inhibits growth of sensitive malignancies, prevents ovulation through inhibition of pituitary gonadotropin secretion, and prevents spontaneous uterine contraction.

Contraceptive treatment of breast cancer; secondary amenorrhea; palliation and adjunctive therapy of inoperable recurrent and metastatic renal and endometrial carcinomas; abnormal uterine bleeding without an organic etiology.

Metabolized in the liver; excretion unclear.