The effectiveness of twice versus once-only membrane sweeping among uncomplicated primi gravidae at 40 weeks of gestation – A randomized controlled trial

Objective To assess the effectiveness and acceptability of twice versus once-only Artificial Sweeping of Membrane (ASM) among uncomplicated primigravidae at 40 weeks of gestation in a tertiary care hospital in Sri Lanka. Methods A randomized controlled trial was performed among 240 uncomplicated primigravidae with ≤5 Modified Bishop’s Score (MBS) at 40 weeks of gestation at teaching hospital Kandy from August 2013 to May 2014. Following randomization both groups received ASM at 40 weeks of gestation and the intervention group received a repeat ASM after 48 hours (40 weeks +2 days). The MBS was re-assessed at 40 weeks +5 days. Participants who did not have spontaneous onset of labor (SOL) at 40 weeks +5 days were managed according to the ward policy of cervical ripening and Induction of Labor (IOL). Perceived discomfort, acceptability of the method, neonatal, maternal and labour outcomes were assessed. Results More participants in the intervention group established SOL within 48 hours compared to the controls (61.6% vs. 45%, RR=1.37, 95% CI=1.1-1.7, NNT=6). However, the difference of the mean MBS among the participants who had not delivered at 40+5 days, between the two groups was not statistically significant [mean MBS=6.36 (SD=1.94) in intervention group and 6.03 (SD=0.84) in control group; p=0.354]. There was no significant difference among the participants who would recommend either method to another patient (75% in intervention vs 79.1% in control groups, RR=0.94, 95% CI=0.8-1.1) and who would accept either method during a subsequent pregnancy (72.5% in both groups, RR=1, 95% CI=0.9-1.2). Participants who required IOL at 40 weeks +5 days was significantly lower among the intervention group (38.4%; compared to 55% in controls) with RR=0.69 (95% CI=0.5-0.9). There were no significant differences in neonatal, labour outcomes, and maternal complications between the groups. Conclusions and recommendations Twice sweeping of membrane reduced the need of IOL and increased progression towards SOL at 40 +5 days. Acceptability of twice sweeping is not different from sweeping once. We recommend twice membranes sweeping as first line management for induction for women at 40 weeks gestation.