[Progestagen and contraceptive activity of a 16alpha-methylene derivative of progesterone].

Data of experimental character reflecting the pharmacological activity of 16alpha-methylene derivative of progesterone--melengesterol acetate--are presented. A high progestagenic activity of the preparation was revealed in a series of tests, namely, the appearance of secretory changes in the uterine endometrium of infantile female rabbits and persistence of pregnancy in ovariectomized rabbits. A high contraceptive activity not accompanied by suppression of ovulation was found in administration of the preparation in low doses combined with mestranol.