Mifepristone in second-trimester medical abortion: a randomized controlled trial

Abstract

Objective: To investigate the adjunctive use of mifepristone in second-trimester induction abortions using misoprostol 1 day after feticidal digoxin.

Methods: This is a randomized, placebo-controlled, double-blind trial of mifepristone in second-trimester induction termination using misoprostol after feticidal digoxin. Women seeking abortion between 18 and 23 weeks of gestation were offered enrollment. At the time of digoxin amnioinfusion, participants received a randomly allocated, identical-appearing capsule containing either mifepristone, 200 mg, or placebo. Patients returned the following day for induction with buccal misoprostol. The primary outcome was the time interval from the first misoprostol dose to abortion. Analysis utilized survival curves with log-rank testing.

Results: Of 64 women, 32 received mifepristone and 32 received placebo. The groups did not differ by ethnicity, age, parity, reason for termination, or gestational age. Median procedure time was significantly shorter for those who received mifepristone, 10 hours (95% confidence interval [CI] 8-12), than those who did not, 18 hours (95% CI 15-22), P<.01, and those parous, 10 hours (95% CI 9-14), compared with nulliparous, 16 hours (95% CI 12-22, P=.02). Other findings in the mifepristone compared with placebo group included rates of placental retention, 3.1% compared with 6.3% (P=.61), length of hospitalization, 0.66 days compared with 0.8 days (P=.23), and analgesic requirements, 27.2 mg compared with 39.3 mg morphine (P=.22). Side effects during induction were similar between groups.

Conclusion: Addition of mifepristone in second-trimester termination inductions using misoprostol significantly reduces the abortion time interval.

Clinical trial registration: Clinicaltrials.gov, www.clinicaltrials.gov, NCT00382538

Level of evidence: I.