Methotrexate and misoprostol for early abortion

Abstract

Methotrexate is cytotoxic to trophoblast and, in low doses, has minimal side effects. It is used to treat both gestational trophoblastic neoplasia and ectopic pregnancy. The cytotoxic effects of methotrexate on intrauterine trophoblast should be equivalent. To test this hypothesis, ten pregnant women, < 8 weeks' gestation were reated with methotrexate 50 mg/m 2 intramuscularly followed 3 days later by misoprostol, a prostaglandin E 1 analogue. The first 4 patients received misoprostol 600 μg orally; none aborted soon after the misoprostol. Two patients aborted 25 and 26 days after the methotrexate injection and two elected a suction abortion after 14 days (one by choice and one because the pregnancy was still viable). The last 6 patients received misoprostol 800 μg vaginally and aborted within 3–8 hours. One patient had an incomplete abortion requiring a suction curettage 34 days after the misoprostol. Vaginal bleeding for these 6 patients lasted an average of 29 ± 11 days (range, 12–42 days). No methotrexate side effects were observed. Vaginal misoprostol (800 μg) was significantly more effective (p = 0.005) than oral misoprostol (600 μg) in effecting abortion after intramuscular methotrexate.