Lactation inhibition with chlormadinone and mestranol

12 women were administered the contraceptive preparation Ovosiston which consists of 3 mg of chlormadinone and .1 mg of mestranol and another 132 were given Femigen-Polfa which contains 2 mg of chlormadinone acetate and .05 mg of mestranol. All subjects were administered 3 tablets daily in the first 2 periods decreasing to 2 tablets and finally 1 tablet until 25 days before the laying in. The level of lactation was measured throughout this period. The use of chlormadinone and mestranol was found to be an effective method of inhibiting and depressing lactation through its ability to liquidate secretions from the uterus. Femigen was found to be more swiftly acting than Ovosiston takin effect in 24 hours. Catamnesis showed that these preparations have a detrimental effect on subsequent menstrual cycles.