Midtrimester abortion induced by serial intramuscular injections of 15(S)-15-methyl-prostaglandin F2alpha.

Midtrimester abortion was successfully induced in 35 patients by serial intramuscular injections of 15(S)-15-methyl-prostaglandin F2alpha. The dose schedule in this series was an initial injection of 250 mug of 15-ME-PGF2alpha followed by another 250 mug in 2 hours, then 500 mug every 2 hours up to 24 hours; in patients who did not abort within 24 hours the dose was raised to 750 mug every 2 hours until abortion. The mean abortion time was 15.98 hours in this series and 86 per cent of the patients aborted in under 24 hours. Parous patients aborted faster (mean 14.81 hours) than nulliparous patients (mean 17.02 hours) and patients with lower gestational age, 13 to 16 weeks, aborted more quickly (mean 13.98 hours) than patients with gestational age 17 to 20 weeks (mean 16.35). These differences in this series, however, were not statistically significant. Gastrointestinal side effects occurred in 32 of the 35 patients and eight patients had a temperature elevation of more than 1 degree F. during the treatment period. The mean estimated blood loss was 137 plus or minus 42 ml. Thirty patients passed the fetal-placental unit intact, the placenta was removed by sponge forceps in three patients, and by surgical intervention in two patients. There were no failures of technique in this study and none of the patients developed endometritis.