To Identify Risk Factors Predicting Spontaneous Preterm Labor Less Than 28 Weeks After Emergency Cerclage in the Second Trimester of Pregnancy

Abstract Purpose To identify risk factors predicting spontaneous preterm labor (sPTB) less than 28 weeks after emergency cerclage in the second trimester of pregnancy.Methods 106 cases with Prolapsed membranes in the second trimester of pregnancy who underwent emergency cerclage were collected from July 2019-July 2021 .39 cases who happened sPTB less than 28 weeks were in case group. 67 cases were in control group.Univariate analysis and logistic regression analysis were used to identify the risk factors for sPTB less than 28 weeks after emergency cerclage.Results Among the 106 cases,37cases developed sPTB less than 28 weeks, and the incidence was 36.8%, Univariate analysis showed that positive cervical culture,cervical dilatation,the location of amniotic membranes and histologic chorioamnionitis were related with sPTB(P<0.05). Logistic regression analysis showed that histologic chorioamnionitis was the risk factors for sPTB after emergency cerclage in patients with Prolapsed membranes in the second trimester of pregnancy[relative risk14.603 ,95% confidence interval(CI)2.621-81.369,P<0.05].Amniotic membrane is an independent risk factor for less than 28 weeks of sPTB after emergency cerclage in middle pregnancy [relative risk11.993 ,95% confidence interval(CI)3.825-37.607,P<0.05].Conclusion The independent risk factors of sPTB less than 28 weeks after emergency cerclage with prolapsed membranes in the second trimester of pregnancy was histologic chorioamnionitis and Amniotic membrane.