Delivery, mode of Archives - Revista Brasileira de Ginecologia e Obstetrícia

Purpose: to investigate antepartum factors related to cesarean section and develop a cesarean section predictive model. Methods: the study design was a retrospective cohort which included all the cared 843 deliveries in a third level unit from June 1993 through November 1994. Children with 1,000 g birthweight and above were included. The dependent variable was cesarean section (c-section). Independent variables were antepartum factors related to c-section. Logistic regression was used to develop a predictive model. Results: our model showed risk of c-section according to the following variables: maternal age under 20 years (OR = 0.396) and over 28 years (OR = 2.133); previous vaginal deliveries (OR = 0.626); previous c-section (OR = 4.576); prenatal care (OR = 2.346); breech presentation (OR = 4.174); twin pregnancies (OR = 14.065); late obstetrical hemorrhage (OR = 28.189); mild preeclampsia (OR = 2.180); severe preeclampsia OR=16.738; chronic hypertension OR=4.927 and other clinical problems (OR = 2.012). The predictive model had a concordance of 82.3% between probabilities and responses. Conclusions: our study identified 12 antepartum factors related to c-section. It was possible to develop a cesarean section predictive model taking into account all previously identified antepartum risk factors.