Postpartum Hemorrhage Following Cesarean Delivery in Women with a Scarred Uterus: A Retrospective Cohort Study

Objective: To develop a model to predict the risk of postpartum hemorrhage (PPH) following cesarean delivery in women with a scarred uterus.Methods: A total of 4,637 pregnant women with scarred uterus who underwent a cesarean delivery at a large hospital between January 2014 and December 2017 were enrolled. The women were divided into PPH (n = 287) and non-PPH (n = 4,350) groups. A model to predict PPH (blood loss ≥1,000 mL within 24 h following cesarean delivery) was developed using multivariate logistic regression analysis. Receiver operating characteristic curve was drawn, and the area under curve (AUC) was calculated.Results: The incidence of PPH was 6.19% (287 of 4,637 women). Seven independent risk factors were associated with PPH: maternal age (odds ratio [OR]= 1.42, 95% confidence interval [CI]: 1.02-1.97), previous gravidity (OR = 1.24, 95%CI: 1.01-1.50), placental location (posterior wall of uterus,OR= 0.69, 95%CI: 0.47-1.02; other locations,OR= 1.21, 95%CI: 0.81-1.80), placenta previa (incomplete placenta previa,OR = 10.51, 95%CI: 5.99-18.42; complete placenta previa,OR = 31.65, 95%CI: 21.07-47.54), placenta accreta (OR = 6.39, 95%CI: 4.02-10.16), hypertensive disorders of pregnancy (OR = 2.27, 95%CI: 1.40-3.68), and fetal position (breech position,OR = 2.07, 95%CI: 1.19-3.60; transverse position,OR = 1.07, 95%CI: 0.48-2.41). A predictive model with AUC of 0.89 was developed (95%CI: 0.86-0.91,P < 0.001).Conclusions: A model was developed to predict PPH following cesarean delivery in women with a scarred uterus.