Pain Associated With Cervical Priming for First-Trimester Surgical Abortion A Randomized Controlled Trial

OBJECTIVE: To compare the effect of cervical priming with mifepristone with that of misoprostol on pain perception during surgical induced abortion under paracervical block. METHODS: We conducted a randomized, single-blind, two-center study of women undergoing surgical induced abortion at less than 14 weeks of gestation under paracervical block. Participants were randomized to receive cervical priming with 200 mg of oral mifepristone 36 hours or 400 micrograms buccal misoprostol 3 hours before surgery. The primary outcome was pain during mechanical cervical dilation evaluated by a 100-mm visual analog scale (VAS). Secondary outcomes were pain during aspiration, preoperative and postoperative pain, participant satisfaction, duration of the procedure, occurrence of complications, and ease of performing the procedure (assessed by a 100-mm VAS). We estimated that 110 women would have to be included to have 90% power to detect a 13mm-difference of VAS for pain. RESULTS: Between June 2017 and May 2019, 314 women were eligible and 110 were randomized (55 in each group). Patient characteristics were similar in the two groups. The mean VAS score during mechanical cervical dilation was lower in the mifepristone group (35.6 +/- 21 vs 43.5 +/- 21, P=.04) as was the mean VAS during aspiration (34 +/- 24 vs 47.8 +/- 23, P=.003). The preoperative and postoperative mean VAS, satisfaction and duration of procedures were similar between groups. The procedure was significantly easier to perform in the mifepristone group (88 +/- 16 vs 80 +/- 23, P=.004). CONCLUSION: Cervical priming with mifepristone for surgical induced abortion under paracervical block up to 14 weeks of gestation is more effective than misoprostol in reducing pain perception.