Twice-Weekly Versus Once-Weekly Membrane Sweeping in the Prevention of Post-Term Pregnancy: a Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Membrane sweeping is considered a simple and effective method for initiating spontaneous onset of labor. Despite the widely accepted membrane sweeping use to prevent post-term birth, the optimal frequency has not been estimated. We aimed to assess the effectiveness and safety of twice-weekly versus once-weekly membrane sweeping in post-term pregnancy prevention. Four different databases were searched for available clinical trials from inception to October 2022. We selected randomized controlled trials (RCTs) that compared twice-weekly membrane sweeping in intervention group versus once-weekly membrane sweeping in control group among pregnant women with singleton pregnancy at ≥ 39 gestational weeks. Our primary outcomes were the rate of spontaneous onset of labor and the requirement for formal methods of labor induction. Our secondary outcomes were sweeping to delivery interval in days, gestational age at delivery in weeks, Bishop score at admission, chorioamnionitis, and premature rupture of membranes. Three RCTs (596 patients) were included. Twice-weekly membrane sweeping was associated with significant increase in the rate of spontaneous onset of labor and significant decline in labor induction rate in comparison with once-weekly group. Duration from sweeping to delivery was significantly shorter among the twice-weekly group (p<0.001). Furthermore, gestational age at delivery was significantly earlier in the twice-weekly group. A significantly higher Bishop score at admission was observed in the twice-weekly group (p=0.02). There were no significant differences across both groups in chorioamnionitis and premature rupture of membranes. In conclusion, twice-weekly membrane sweeping is more effective in preventing post-maturity pregnancy than once-weekly sweeping without added adverse events.