Induction of abortion in early first trimester human pregnancy using epostane.

The role of epostane (Sterling Winthrop, Guildford, UK), a competitive inhibitor of the 3 beta hydroxysteroid dehydrogenase enzyme system (3 beta-HSD), as an abortifacient agent in early human pregnancy has been studied in 54 women. All were less than 49 days from their last menstrual period. Thirty were treated with 200 mg of epostane every 8 h for 7 days and 24 were given 200 mg every 6 h for 7 days. This caused a sustained reduction in circulating progesterone concentrations, a smaller fall in 17 beta-oestradiol and no effect on serum cortisol. Abortion occurred in 21 women (70%) in the lower dosage group and in 20 women (87%) in the higher dosage group. Abortion was incomplete in 6 of these 41 women. A worsening of pregnancy nausea and vomiting was noted by 66% of women in the first group and 84% in the second. There was no delay in the resumption of normal menstruation following abortion. This study confirms the potential of epostane as an effective inhibitor of ovarian and placental steroidogenesis and as a potent abortifacient agent in early human pregnancy.