Methotrexate and misoprostol for early abortion: A multicenter trial. I. Safety and efficacy

A prospective trial was conducted including 300 pregnant women seeking elective abortion to evaluate the safety and efficacy of methotrexate and misoprostol for abortion at ≤56 days gestation. Subjects received methotrexate 50 mg/m² intramuscularly followed 7 days later by misoprostol 800 μg vaginally. The misoprostol dose was repeated the next day if the abortion did not occur. Outcome measures included successful abortion (complete abortion without requiring a surgical procedure), duration of vaginal bleeding, and side effects. Complete abortion occurred in 263/300 (87.7%, 95% CI 83.4, 91.2%) patients. The complete abortion rate was higher for early gestations: 183/202 (90.6%, 95% CI 85.7, 94.2%) at ≤49 days gestation, and 80/98 (81.6%, 95% CI 72.5, 88.7%) from 50-56 days gestation (p=0.038). Abortion occurred in the 24 hours following the initial or repeat misoprostol dose (immediate success) in 65.0%; the remaining 22.7% of women who aborted did so after a delay of 23.6 ± 9.1 (mean ± standard deviation) days. Vaginal bleeding lasted 14 ± 7 days and 11 ± 9 days in immediate success and delayed success patients, respectively. Overall, 69.7%, 87.7%, and 91.7% of patients had passed the pregnancy by 14, 28, and 35 days, respectively, after receiving methotrexate. Methotrexate and misoprostol side effects were minimal. This treatment regimen offers an alternative to surgical abortion or the use of antiprogestins and prostaglandin for medical abortion.