[Steroid and nonsteroid postcoital contraceptives].

It has been shown experimentally that a combined use of estrogen-norsteroids prostaglandins and neurotropic substances during preimplantation period produces the most potent contraceptive effect. Analysis of the action mode of combined small doses of steroids, prostaglandins and neurotropic drugs suggests that the contraceptive action is underlain by the inhibitory effect on incretion produced by the luteinizing hormone, this effect being in its turn a reason for variation in the amount and condition of the developing fetuses.