Study On The Risk Assessment Model Of Trial Of Labor After Cesarean Section

Objective(1) This study aims to investigate the risk factors affecting the outcome of Trial of labor after cesarean, and analysis the interaction between various the factors, then provide a theoretical basis for constructing a model to predict the risk of Trial of labor after cesarean.(2) To built a model to predict the outcome of trial of labor after cesarean, which is suitable to be used by local people, and to provide a theoretical reference for choosing delivery mode for pregnant women with a history of cesarean.Method This study was conducted from January 1, 2010 to December 31, 2015 in the First Affiliated Hospital of Jinan University, 216 cases of pregnant women with a history of cesarean was included. The vaginal delivery group included 182 cases and 34 cases fail of an atrial of labor. The factors that might affect the outcome of vaginal delivery were analyzed by single factor analysis firstly, then Logistic regression analysis was performed with the influencing factors above and other important predictive variables, then we built a model to predict the outcome of Trial of labor after cesarean based on the significant factors, which is suitable to be used by local people. Finally, evaluate goodness of fit of the model and its accuracy.Results(1)single factor analysis showed that there were six risk factors related to the outcomes of Trial of labor after cesarean, maternal height, neonatal weight, admission BMI, scar time, admission labor, the history of vaginal delivery, but maternal age, gestational weeks, uterine scar muscle layer thickness were not risk factors for the vaginal delivery outcome.(2) Logistic regression analysis showed that there were five risk factors related to the outcomes of Trial of labor after cesarean, such as the history of vaginal delivery(OR=3.23, 95% CI:1.65~4.13), admission labor(OR=2.48, 95% CI:1.12~ 3.56), neonatal weight<3500g(OR=2.12, 95% CI:1.16 ~3.31), scar time<7y(1.17, 95%(3)CI:1.01 ~1.68), maternal height >155cm(OR=0.82, 95% CI:0.31~0.96).(4) The prediction model product by logistic regression to predict the outcome of Trial of labor after cesarean: P=1/(1 + exp(1.640+2.83 prior vaginal delivery history + 2.05 admission labor + 1.72 neonatal weight + 1.03 scar time- 0.95 of maternal height)(5) The total accurate rate of the regression model was 86.6%, the sensitivity was 89.6%, and the specificity was 70.6%.Conclusions(1) Analysis of the influencing factors that had a history of vaginal delivery, admission of labor,neonatal birth weight less than 3500 g, scar time limit of less than 7 years, maternal height > 155 cm is a favorable factor for vaginal delivery after cesarean section, the above factors has the objectivity that can provide theoretical support for the prediction model of vaginal delivery.(2) This study used the Logistic regression method to establish a model to predict the outcome of Trial of labor after cesarean, and has a certain practical value for clinical screening suitable person for vaginal delivery after cesarean section, but only used back to the evaluation method to predict performance of the mode. It means that this model’s extrapolation has certain limitation and needs further validation and improvement..