Abstract
INTRODUCTION: Data with a high level of evidence is lacking on the use of prophylactic uterotonic drug following vaginal delivery to prevent postpartum hemorrhage (PPH) among women who were considered high-risk for PPH. Our main objective was to compare the effectiveness of prophylactic carbetocin versus oxytocin in preventing PPH after vaginal delivery among women at high risk. MATERIAL AND METHODS: We conducted a retrospective before-and-after single-center comparative study, including all high-risk women after vaginal births. Two consecutive 14-month periods were compared, where the prophylactic methods to prevent PPH differed: oxytocin (5 IU IV) versus carbetocin (100 μg IV) given immediately after vaginal delivery. High-risk women were defined by at least one of the following criteria: previous PPH (blood loss ≥500 mL), antenatal suspicion of macrosomia (estimated fetal weight >90th p), twin pregnancy, repeated cervical ripening methods, polyhydramnios, multiparity (≥4), and rapid labor (<2 h) without analgesia. The primary outcome was PPH. Secondary outcomes included severe PPH (blood loss ≥1000 mL), second-line uterotonic agents, surgical hemostatic procedures, uterine artery embolization, and maternal morbidity. Groups were matched 1:1 by risk criteria. Outcomes were assessed using univariate analysis, multivariable logistic regression, and propensity score adjustment. RESULTS: A total of 754 women (377 per group) were included. Maternal and labor characteristics were comparable. Rates of PPH and severe PPH were similar with carbetocin versus oxytocin (7.4% vs. 9.3%, p = 0.36; 2.9% vs. 2.7%, p = 0.83). The need for second-line uterotonics (additional oxytocin and/or sulprostone) was significantly lower with carbetocin (3.7% vs. 12.2%, p < 0.001). Other secondary outcomes did not differ. After adjustment for potential confounders (history of PPH, BMI, intrapartum fever), prophylactic carbetocin was not associated with increased risk of PPH (aOR = 1.85, 95% CI [0.97 to 3.57]). Propensity score analysis confirmed these findings (aOR = 1.33, 95% CI [0.74 to 1.72]). CONCLUSIONS: Prophylactic carbetocin was associated with a similar rate of PPH in high-risk women after vaginal delivery, compared with oxytocin, but significantly reduced the use of oxytocin when carbetocin was used as the first-line agent, although there was no difference in the use of prostaglandins or invasive procedures to manage persistent PPH.