Cesarean Scar Pregnancy and Subsequent Obstetric Outcomes: Focus on Postpartum Hemorrhage and Predictive Factors

BACKGROUND Cesarean scar pregnancy (CSP), a rare form of ectopic pregnancy, is associated with substantial maternal morbidity and uncertain implications for subsequent pregnancies. This study evaluated the association between prior CSP and adverse obstetric outcomes in subsequent pregnancies; it also explored independent predictors of postpartum hemorrhage (PPH). MATERIAL AND METHODS This retrospective single-center study included 15 439 women with prior cesarean section who delivered at a tertiary hospital (January 2015 to December 2023): 83 patients with CSP (Type I: n=24, ultrasound-guided uterine aspiration; Type II/III: n=59, uterine artery embolization [UAE]+aspiration) and 15 356 patients without CSP (non-CSP). Outcomes included PPH and secondary obstetric and neonatal complications. Multivariate logistic regression analysis was performed to address potential confounders. RESULTS CSP was associated with higher rates of PPH (21.7% vs 1.7%; adjusted relative risk [aRR] 2.62, P=0.024), placenta previa (aRR 6.50, P<0.001), placenta accreta spectrum (PAS; aRR 8.31, P<0.001), preterm delivery before 33 weeks (aRR 12.05, P<0.001), and low birth weight (aRR 4.19, P<0.001). Type II/III CSP (adjusted odds ratio [aOR] 17.90, P<0.001), placenta previa (aOR 5.12, P=0.046), and PAS (aOR 12.48, P<0.001) were independent predictors of PPH. UAE did not significantly affect PPH risk (P=0.628). CONCLUSIONS CSP increases the risk of adverse obstetric outcomes. Type II/III CSP, placenta previa, and PAS are predictors of PPH. Prenatal assessments of CSP recurrence and placental disorders are critical for maternal-fetal safety.