Multifactorial Analysis Of The Effect Of Cervical Balloon On Pregnancy Outcome In Full-term Primipara

Objective:To explore the factors that influence the delivery mode in primipara with cervical dilatation balloon,and to establish a model to predict the vaginal delivery.It is helpful to select suitable object to use cervical balloon,reduce clinical intervention,and improve the rate of spontaneous delivery of primipara.Methods:A total of 312 full-term singleton primipara were enrolled from January 2018 to April2019 in Obstetric Department of Shenzhen Second People’s Hospital,including 221 cases of successful vaginal delivery and 91 cases of failed vaginal delivery.The data of age,times of pregnancy,height,weight,body mass index(BMI),indication of induction of labor,complications of pregnancy,weeks of pregnancy during induction of labor with balloon,birth weight,Bishop score before and after placement of cervical dilatation balloon,duration of dilatation balloon,fever during labor,mode of delivery and causes of cesarean section were analyzed.Kruskal Wallis test was used to analyze the influence factors on the success of balloon induced labor.P < 0.05 was defined as statistically significant.Logistic regression analysis was performed on the variables with statistical significance,and ROC curves were drawn.Results:1.Kruskal Wallis test showed there were significant differences in the success rate of balloon induced labor :the height(H=4.182,P <0.05),the weight(H=0.004,P<0.05),BMI(H=3.991,P <0.05),pregnant times(H=11.482,P <0.05)、cervical score(H=0.049,P <0.05)and the birth weight(H=5.393,P <0.05).2.Logistic regression analysis showed that the height of pregnant women(OR1.051,95% CI 1.001-1.103,P < 0.05),the times of pregnancy(OR 1.536,95% CI 1.162-2.031,P < 0.05)and the weight of newborn(OR 0.999,95% CI 0.996-1.000,P <0.05)had statistical significance on the success of induction of labor by balloon.3.The Times of pregnancy,the time of placing the cervical balloon,the weight of the newborn,the fever with or without birth had statistical significance on the success of using the cervical dilatation balloon for induction of labor in term Singleton Primipara.The area under the ROC curve was 0.672,(95% CI 0.603-0.741).The optimal threshold was 0.331,the specificity was 0.76,the sensitivity was 0.429,and the accuracy was 0.663.Conclusion:1.The higher the times of pregnancy and the higher the height of primipara,the higher the successful rate of labor induction.2.When the newborn’s weight ≤3250g,with the increase of the newborn’s weight,the success rate of induction of labor by balloon was increased.When the birth weight was more than 3250 g,the success rate of induction of labor by balloon was decreased with the increase of the birth weight.3.Cervical dilatation balloon is more effective in promoting cervical ripening in primipara with low cervical score.4.Logistic regression analysis showed that the times of pregnancy,the height of the pregnant woman and the weight of the newborn were the important factors affecting the outcome of cervical dilatation,which could be used to predict the success rate of cervical dilatation.