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

Contraception. 1996 Jun;53(6):321-7. doi: 10.1016/0010-7824(96)00080-7.

Abstract

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 < or = 56 days gestation. Subjects received methotrexate 50 mg/ m2 intramuscularly followed 7 days later by misoprostol 800 micrograms 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 < or = 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.

PIP: Clinical researchers recruited 300 healthy English- and Spanish-speaking pregnant women of gestational age no greater than 56 days for a prospective clinical trial of intramuscular 50 mg/sq. m methotrexate and 800 vaginal mcg misoprostol for induced abortion. The women were recruited from San Francisco General Hospital in California; Magee-Women's Hospital in Pittsburgh, Kansas; and Women's Health Care Services in Wichita, Kansas. 87.7% of the women had a complete abortion without need for a surgical procedure. After administration of methotrexate, passage of the conceptus increased as time passed (69.7% for 14 days, 87.7% for 28 days, and 91.7% for 35 days). The complete abortion rate decreased as the gestational age increased (90.6% for 49 days vs. 81.6% for 50-56 days; p = 0.038). Abortion took place within 24 hours of the first or repeat misoprostol dose in 65% of women who aborted. The success rate after the first dose of misoprostol was higher between 43 and 56 days than before 43 days (54.7% vs. 43.5%; p = 0.07). All women with an incomplete abortion experienced persistent and/or heavy vaginal bleeding. Vaginal bleeding lasted, on average, for 14 days in immediate success cases and for 11 days in delayed success cases. Multivariate logistic regression analysis found a significant predictor of success for the methotrexate and misoprostol combination to be gravidity under 3 (p = 0.01, odds ratio [OR] = 2.6). Serum beta-human chorionic gonadotropin of 40,000-80,000 IU/L (p = 0.025, OR = 0.38) and serum beta-human chorionic gonadotropin of 80,000 IU/L (p 0.001, OR = 0.2) were significant predictors of its failure. The rate of side effects was low. These findings show that this treatment regimen is a safe and effective alternative to surgical abortion or the use of antiprogestins and prostaglandins for medical abortion.

Publication types

  • Clinical Trial
  • Comparative Study
  • Multicenter Study

MeSH terms

  • Abortifacient Agents, Nonsteroidal / administration & dosage
  • Abortifacient Agents, Nonsteroidal / adverse effects
  • Abortifacient Agents, Nonsteroidal / pharmacology*
  • Abortion, Induced / methods*
  • Abortion, Induced / statistics & numerical data
  • Administration, Intravaginal
  • Adult
  • Chorionic Gonadotropin / blood
  • Female
  • Humans
  • Injections, Intramuscular
  • Methotrexate / administration & dosage
  • Methotrexate / adverse effects
  • Methotrexate / pharmacology*
  • Misoprostol / administration & dosage
  • Misoprostol / adverse effects
  • Misoprostol / pharmacology*
  • Odds Ratio
  • Parity
  • Patient Compliance
  • Pregnancy
  • Pregnancy Outcome
  • Pregnancy Trimester, First
  • Prospective Studies
  • Safety
  • Surveys and Questionnaires

Substances

  • Abortifacient Agents, Nonsteroidal
  • Chorionic Gonadotropin
  • Misoprostol
  • Methotrexate