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

ABSTRACT

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.