Comparing Transcervical Balloon with Osmotic Dilators for Cervical Preparation Prior to Procedural Abortion: a Non-Inferiority Randomized Trial.

Abstract

To compare cervical preparation with transcervical balloon to osmotic dilators for second-trimester procedural abortions.We performed an unblinded, randomized, non-inferiority trial of people undergoing second-trimester procedural abortion at 18+0 to 23+6 weeks gestation. We randomized participants to either overnight osmotic dilators (Dilapan-S) or transcervical balloon (Foley). Both groups received overnight mifepristone and pre-procedural misoprostol. We powered the study on mean difference in procedure duration; non-inferiority limit 5 minutes. We compared pre-procedure cervical dilation; need for additional dilation; and, using 100-point visual analogue scale, measured physician satisfaction and ease of procedure, and participant pain and satisfaction.We recruited 32 participants at a single academic center. Although procedure time (minutes) was similar (balloon: 22.6+8.9 vs Dilapan-S: 22.4+12.8, p=0.96), non-inferiority was not met (mean difference, 0.2 minutes; 95% confidence interval, -7.8 to 8.2). Cervical dilation >2cm was more likely after Dilapan-S (100% vs 62.5%, p=0.02). Placement was well tolerated with similar time (minutes) for insertion (balloon: 4.8+1.0, Dilapan-S: 5.1+2.3, p=0.64) and maximum pain (median) with insertion (balloon 39 (5-78), Dilapan-S: 39 (0-100), p=0.92). Pain immediately post-insertion was higher for Dilapan-S (33 (0-100) vs 18 (0-50), p=0.046), and similar for maximum pain overnight, participant satisfaction, and likelihood to recommend. Complications were minor and similar between groups (p=0.60).While significantly more people with transcervical balloon required mechanical dilation, the difference in operative time was clinically negligible. The transcervical balloon was well tolerated and acceptable by participants.Clinicians experienced in mechanical dilation may consider a transcervical balloon as a lower-cost tool for second-trimester abortion cervical preparation.ClinicalTrials.gov: NCT05099991.

View details for DOI 10.1016/j.contraception.2024.110550

View details for PubMedID 39067560