Clinical trials of intramuscular sulprostone for second trimester abortion

Abstract

The synthetic prostaglandin E2 derivative Sulprostone (16-phenoxy-W-17, 18, 19, 20-tetranor) is an effective 2nd trimester abortifacient. This study compares 2 dosage regimens of intramuscular administration. In regimen 1, 9 women with intact pregnancy and 3 with intrauterine fetal death were given Sulprostone 500 mcg 3 times at 4-hour intervals to be repeated after 24 hours if abortion did not occur. In regimen 2, 12 women with intact pregnancies were given Sulprostone 500 ug every 6 hours for up to 6 injections or 3000 mcg. Either regimen was considered a failure if expulsion did not occur within 48 hours. 15 of 21 cases of intact pregnancy were successfully aborted, yielding a total success rate of 71.4%. Regimen 1 was 66.7% successful, with a total dosage of 2250 mcg, and regimen 2 was 75% successful, with a total dosage of 2055 mcg. In regimen 1 the total dose was lower for primigravidas than for multiparas; in regimen 2 it was lower for multiparas. All 3 cases of intrauterine death were aborted after a single course of dosage regimen 1. 2 failures aborted spontaneously after 49 and 80 hours, and 4 were aborted by intraamniotic saline solution. In both regimens side effects (vomiting and diarrhea, chills and fever, dizziness, headache, and dyspnea) were minimal. The 1st regimen is recommended because, if injections are started early in the day, it can be used to induce midtrimester abortion on an outpatient basis.