Cervical pessary to reduce preterm birth before 34 weeks of gestation after an episode of preterm labor and a short cervix: a randomized controlled trial

Background To date, no intervention has proved effective in reducing the spontaneous preterm birth rate in singleton pregnancies following an episode of threatened preterm labor and short cervix remaining. Objective This study was designed to ascertain whether cervical pessaries could be useful in preventing spontaneous preterm birth in women with singleton pregnancies and a short cervix after a threatened preterm labor episode. Study Design This open randomized controlled trial was conducted in 357 pregnant women (between 24 0 –33 6 weeks) who had not delivered 48 hours after a threatened preterm labor episode and had a short cervix remaining (≤25 mm at 24 0 –29 6 weeks; ≤15 mm at 30 0 –33 6 weeks). Patients were randomly assigned to cervical pessary (179) or routine management (178). The primary outcome was the spontaneous preterm birth rate Results No significant differences between the pessary and routine management groups were observed in the spontaneous preterm birth rate P  = .01). Preterm premature rupture of membranes rate was significantly lower in pessary carriers (4/177 [2.3%] vs 14/175 [8.0%]; relative risk, 0.28; 95% confidence interval, 0.09–0.84; P  = .01). The pessary group less frequently required readmission for new threatened preterm labor episodes (8/177 [4.5%] vs 35/175 [20.0%]; relative risk, 0.23; 95% confidence interval, 0.11–0.47; P Conclusion Pessary use did not significantly lower the spontaneous preterm birth rate