Establishing And Applicating Of Modified Prediction Scoring System Of Vaginal Delivery With Uterine Scar

Objective:To investigate factors affecting second vaginal birth after cesarean, analyze the reasonableness of indications of pregnant vaginal trial production in patients with uterine scar, establish the prediction scoring system to assess the risk and indications of vaginal trial production in postpartum patients. Methods: 1. Source: From August 2011 to August 2013, 132 patients among 892 cases with uterine scar, which were informed and met the inclusion criteria, were studied. 93cases proceeded vaginal trial production successfully, but 39 cases need cesarean section. 2. Establish the modified prediction scoring system to predict the outcome of uterine scar pregnancy(modified scoring method): ① preferences: Based on the traditional scoring method--Flamm law and Weitein’s scoring method and Ling Luoda "head position score" and "bishop score,", 13 parameters including age, cervical score, the length of the incubation period, the fetal position, the weight gain after pregnancy and estimated fetal weight were selected to establish the modified prediction scoring system. These parameters were associated to the production outcomes. Prenatal evaluation and real-time monitoring on variables change during production process were taken to get a better prediction. ② The conditions for doctors to judge whether the patients were suitable for vaginal delivery were limited because of the maternal uterine scar. During the trial production process, closely observe and the various score the factors affecting the delivery quantify can help doctors to make more timely and accurate judgment onbirth outcomes and have the correct choice of mode of delivery to reduce obstetric complications. 3. Application of the modified prediction scoring system: ① Applicating the modified prediction scoring system, the enrolled patients with uterine scar were scored under the closely observation of vaginal delivery. ② To draw and compare the area under receiver operating characteristic curve(ROC) among Weitein’s law, Flamm law, modified scoring system. The cutoff value was decided by the best cut-off point basing on the modified scoring method. 4. Grouping Basing on the cut-off point, the relationship between the score and the vaginal trial production outcomes was analyzed. Contrast the second vaginal delivery group whose prediction score was higher than the cutoff value with the first vaginal delivery group with non-uterine scar at the same period. Statistical analysis: All data were presented as means ± SD. The area under the ROC curve was calculated with Simpson’s rule, and was compare by using non-parametric method z test [6]. Vaginal delivery group and cesarean groups were compared by using Wilcoxon test. Count data were compare by using chi-square test or Fisher’s exact test. Software SPSS 19.0 were used to analyze data, and values of P < 0.05 were considered to be significant. Results: 1. The modified prediction scoring system was established by using 13 parameters including age(years), history of vaginal delivery, expected fetal weight(g), cervical dilation(cm), the cervical canal elimination(%), cephalic level, hardness of cervix, position of cervix, strength of contractions, the incubation period(hours), fetal position, weight gain during pregnancy, previous cesarean section. The variable were assigned differently based on whether they were beneficial to vaginal delivery. 2. The area(0.988) under the ROC of modified scoring system was significantly greater than Weitein’s law(0.616) and Flamm Act(0.577).The differences were statistically significant(P <0.05). The best cut-off point of modified scoring system ROC was 18 points. 3. ROC curve, vaginal delivery rate and birth outcomes of modified scoring system: Vaginal delivery rate among patients whose scores were more than 18 is higher than those under 18, 94.8% and 5.6% respectively. The difference was statistically significant(P <0.05). The score of vaginal delivery group(96 cases) was significantly higher than cesarean section group(36 cases), 22.33 ± 1.94 and 14.35 ± 1.87 respectively. The difference was statistically significant(P <0.05). The difference of vaginal delivery success rate, average labor, intrapartum, and postpartum vaginal bleeding 24 hours, Apgar score, puerperal infection and length of stay between patients with uterine scar(96 cases) which score were higher than 18 and patients with non-scarred uterus(100 cases) were not statistically significant (P> 0.05). Conclusions: 1. Establish a modified scoring system containing 13 parameters to predict pregnancy outcome in patients with uterine scar. 2. The modified scoring system had higher diagnostic efficiency than the traditional method. It can better assess the outcome of vaginal trial production after cesarean in second pregnancy. Strict control of indications to enroll vaginal trial production with uterine scar can improve the diagnosis, reduce maternal and child injury, reduce the cesarean section rate, and improve the quality of obstetric.