[Prophylactic medication to prevent miscarriage in pregnant women with a history of sterility (author's transl)].

A report is given of the outcome of 451 pregnancies occurring among women who had previously attended the Infertility Clinic. General gestagen therapy was given prophylactically in 129 cases before the appearance of any signs of threatened abortion. Massive gestagen therapy was initiated in 41 cases in response to signs of threatened abortion. Gestagen was not given either prophylactically or therapeutically in the remaining 281 pregnancies. The incidence of abortion was 10.1% in women given prophylactic gestagen, whilst the overall rate of abortion in the entire series of 451 women was 13.3%. It transpired on closer scrutiny of the 129 cases given prophylactic gestagen therapy that the abortion rate was 12.0% in the 108 pregnancies in which prophylactic gestagen therapy had been initiated at the time of the first missed period or later, whereas not one single abortion was registered amongst the 21 women who had been given gestagen therapy in the immediate post-ovulatory phase. It can be concluded that commencement of prophylactic gestagen therapy at the earliest possible moment provides optimum conditions for successful implantation of the fertilized ovum, especially in cases with masked insufficiency of the corpus luteum.