The effects of intramuscular injections of 15(S)-15-methyl prostaglandin F2alpha in failed abortions.

Intramuscular injections of 15(S)-15-methyl prostaglandin F2alpha (15-Me-PGF2alpha) induced abortion in 38 patients who had failed to abort with other techniques, such as intra-amniotic instillation of saline or PGF2alpha and intravaginal insertion of prostaglandin-impragnated Silastic devices. The intramuscular injections of 15-Me-PGF2alpha were initiated when the original abortion techniques, even when augmented by intravenous oxytocin, failed to produce expulsion of the fetus. The dose schedule was 250 microgram or 500 microgram every 2 to 4 hours, and the concomitant intravenous oxytocin was continued at a rate of 167 mU/minute. Of the 38 patients, 26 aborted with two or fewer injections of 15-Me-PGF2alpha, and 30 patients required only 1 mg of the drug to expel the fetus successfully. The mean time from the first injection of 15-Me-PGF2alpha to the expulsion of the fetus was 5.25 hours; one-half of the patients aborted in less than 4 hours. The placenta was expelled spontaneously in 15 patients, removed manually from the vagina in 18, and removed by sponge forceps in 3. Two abortions were incomplete and surgical intervention was required. Twenty-eight patients (74%) experienced gastrointestinal disturbances, chiefly vomiting and diarrhea. Intramuscular administration of 15-Me-PGF2alpha eliminates the need for repeated amniocentesis, and the dose may be adjusted to meet the precise requirements of the clinical situation.