Objective: To study the effect of mifepristone for priming and induction of second-trimester abortion in conjunction with a high-concentration oxytocin drip.
Study design: Prospective, randomized, placebo-controlled, pilot study. Thirty patients with 14-25 weeks' gestational age abortion received either 600 mg of mifepristone or placebo in 3 identical capsules followed, 48 hours later, by a high-concentration oxytocin drip (HCOD).
Results: The mifepristone group showed significantly higher success rates as compared to the placebo group (92.3% vs. 52.9%, p<0.05). The time interval to abortion (from beginning of HCOD) was also significantly shorter in the mifepristone group as compared to the placebo group (11.3 +/- 6.0 hours vs. 17.6 +/- 6.5 hours, p <0.05). Probability of success as calculated by the Kaplan-Meier method was found to be highly significant (log rank test p = 0.001).
Conclusion: Our results suggest that mifepristone is very effective for priming and induction of second-trimester abortion and shortens significantly the time interval to evacuation following HCOD.