Termination of early pregnancy by the 3 beta-hydroxysteroid dehydrogenase inhibitor epostane.

Progesterone is essential to sustain pregnancy in the first eight weeks. Its synthesis requires the enzyme 3 beta-hydroxysteroid dehydrogenase (3-HSD). We tested the efficacy of an orally administered 3-HSD inhibitor, epostane, in terminating unwanted early pregnancy. Fifty women in the fifth through eight weeks of pregnancy took epostane (200 mg orally every six hours) for seven days. By day 14, pregnancy had been terminated in 42 of the 50 patients (84 percent). Eight women (16 percent) did not abort and underwent dilation and curettage. Vaginal blood loss occurred on average on the third day of epostane treatment, and abortion on the fifth day. Two patients had incomplete abortions; one required a transfusion because of blood loss. Nausea was frequent (in 86 percent), but 76 percent of the participants concluded that epostane was preferable to dilation and curettage. The mean (+/- SD) pretreatment progesterone level (76 +/- 16 nmol per liter) decreased by day 7 (to 16 +/- 11 nmol per liter) and day 14 (to 10 +/- 9 nmol per liter) in those who aborted; levels of human chorionic gonadotropin also decreased from the mean at base line (73 +/- 72 kIU per liter) to 18 +/- 7 kIU per liter on day 7 and 9 +/- 5 kIU per liter on day 14. In those who did not abort after epostane treatment, progesterone levels decreased only slightly by day 7 (to 52 +/- 21 nmol per liter) and rose again (to 81 +/- 18 nmol per liter) by day 14. Among women who responded to epostane, normal menstrual periods had resumed by day 42 after the beginning of treatment in 72 percent. We conclude that epostane taken orally is an effective and safe method for the noninvasive termination of undesired early pregnancy.