A randomized controlled trial evaluating same-day mifepristone and misoprostol compared to misoprostol alone for cervical preparation prior to second-trimester surgical abortion

Objective We evaluated initial cervical dilation with the addition of oral mifepristone to vaginal misoprostol as cervical preparation for same-day second-trimester dilation and evacuation (D&E). Study design Women desiring abortion between gestational ages 14 weeks 0 days and 19 weeks 6 days were randomized to 200-mg mifepristone or identical placebo immediately followed by 400-mcg misoprostol vaginally 4–6 h prior to D&E. Primary outcome was cervical dilation assessed by largest Hegar dilator passed without resistance. Secondary outcomes included total procedure time and participant and provider perceptions. We had 90% power to detect a 2-mm change in initial cervical dilation with a mean of 10 mm (SD = 3.0 mm), requiring 48 participants in each arm. Results Of 100 women enrolled, 96 were randomized and completed the study. Age, race, gestational age (mean 17.4 weeks, SD = 1.3) and parity did not significantly differ. Mean initial Hegar dilation measurements were 11.7 and 10.9 mm in the mifepristone and placebo groups, respectively, with difference of 0.8 [95% CI =−0.4, 2.0 mm]. We found total procedure times of 11.8 and 13.0 min, respectively (difference of 1.2 min [95% CI =−2.4, 4.8 min]. Participant and provider perceptions did not differ. All 96 procedures were completed without hemorrhage, cervical laceration or other observed complications. Conclusion The addition of mifepristone to vaginal misoprostol did not provide a significant increase in cervical dilation compared to misoprostol alone as cervical preparation 4–6 h prior to D&E at 14 weeks through 19 weeks 6 days. Implications Adding mifepristone for a short interval (4–6 h) did not improve cervical preparation with misoprostol prior to D&E at 14–19 weeks. Future studies should evaluate alternative timing intervals of medications for this purpose.