Termination of early gestation with a single vaginal suppository of (15S)-15-methyl-prostaglandin F2alpha methyl ester.

Abortion was induced in 20 women who were less than 49 days pregnant with a vaginal suppository containing 3.0 mg (15S)-15-methyl-prostaglandin F2alpha methyl ester. Peripheral serum levels of (15S)-15-methyl F2alpha free acid, beta hCG and progesterone were measured before, during the 10 hours after treatment and over the next 14 days. Eighteen of the subjects had a complete follow-up: ten were aborted (53%), three had incomplete abortions and five were failures. There was a correlation between serum levels of F2alpha (15S)-15-methyl-prostaglandin F2alpha free acid, and the incidence of success. Progesterone was significantly reduced in all three groups of subjects and, therefore, could not be utilized to judge the success of the procedure. A small but insignificant reduction of betahCG occurred in all subjects regardless of outcome during the ten-hour observation period. Since minor side effects of diarrhea and vomiting occurred in less than half of the aborted and only a few of the not aborted subjects, a larger amount of drug might improve the success rate.