Mifepristone versus vaginally administered misoprostol for cervical priming before first-trimester termination of pregnancy: A randomized, controlledstudy

OBJECTIVE: This study was undertaken to compare the effectiveness of mifepr istone orally administered at 24 or 48 hours before first-trimester vacuum aspiration abortion with that of vaginally administered misoprostol as a ce rvical priming agent. STUDY DESIGN: In a randomized comparative trial 90 women who requested surg ical termination of pregnancy were randomly assigned to receive 200 mg mife pristone orally 24 or 48 hours before the operation or 800 mug misoprostol vaginally 2 to 4 hours before the operation. The main outcome measures were baseline cervical dilatation, cumulative force required to dilate the cerv ix to 9 mm, and intraoperative blood loss. RESULTS: The baseline cervical dilatation was significantly greater among w omen who received mifepristone 48 hours before the operation (P=.02). This group also required the least mechanical force to dilate the cervix (P=.06) . There were no significant differences among the 3 groups in the intraoper ative blood loss, in the operating time, or in patient acceptability. Side effects such as hot flushes and headaches were significantly higher among w omen who received mifepristone 24 or 48 hours before the operation than amo ng those who received misoprostol (P=.01 and P=.002, respectively). CONCLUSION: Mifepristone is an effective cervical priming agent when orally administered 48 hours before vacuum aspiration for termination of first-tr imester pregnancy. Because of its cost and availability in comparison with misoprostol, however, selective use may have to be considered.