Intrauterine extra-amniotic 15(s)-15-methyl prostaglandin f2 alpha for induction of early midtrimester abortion.

Twenty-six patients 13 to 15 weeks pregnant received extraovular 15(S)-15-methyl prostaglandin F2 alpha in a dosage of 1 mg every 18 to 24 hours for three doses. Twenty-five (96%) of the patients aborted; fifteen patients aborted incompletely. The mean induction-to-abortion time was 15.8 hours. A decrease in plasma progesterone levels could not be consistently correlated with abortifacient activity, and there was no statistically significant relationship between abortion time and parity or gestational age. One patient failed to abort after 36 hours of therapy and was aborted by curettage. She was the only patient who developed a postabortion uterine infection. Results with the extraovular technique appear to be similar to those with the intra-amniotic and the intramuscular prostaglandin techniques. Therefore, extraovular administration may be useful for inducing abortion in patients who are in the early midtrimester of pregnancy.