Assessment of success factors in normal vaginal delivery in late term pregnant women

Background: The aim of this study was to find the causes of failure of natural childbirth in late-term pregnancy that can be useful for managing childbirth in these pregnant mothers and to design a solution to increase natural childbirth. Methods: This cross-sectional study was conducted in the community of pregnant women with a late-term pregnancy of more than 41 weeks. The studied sample includes 148 pregnant mothers who were referred to Ayatollah Rouhani Hospital in Babol from March 2018 to February 2020. Mother's age, Body Mass Index, gestational age, number of pregnancies, number of deliveries, length of hospitalization, the state of the cervix and preparation method of the cervix for termination of pregnancy were extracted and recorded from patients' files. Data were compared in two groups of pregnancy termination methods (natural childbirth and cesarean delivery). Statistical analysis was done using SPSS software, version 22 (IBM SPSS, Armonk, NY, USA) and Chi-square test and Student’s t-test statistical tests and logistic regression model fitting. P-value less than 0.05 was considered significant. Results: In this study, 167 pregnant women with late-term pregnancy were studied. The age of pregnant women is reported with mean of 26.03 and standard deviation 5.98 of years. The high Bishop variable, with odds ratio of 0.44, is a variable protective factor for cesarean delivery (P=0.001). Higher body mass index with odds ratio of 1.09, is also known as a risk factor for cesarean delivery (P=0.01), so that for each unit of increase in Bishop score, the chance of cesarean delivery decreases by 56% and for each unit of increase in body mass index, the chance of cesarean delivery increases by 9%. Conclusion: This study showed that nearly half of cases of late pregnancies lead to normal delivery. High body mass index reduces the chance of normal delivery in late term pregnancies. But a higher Bishop score can be effective in the success of natural delivery.