Maternal Perioperative Outcomes with Carbetocin Versus Oxytocin in High-Risk Women Undergoing Elective Cesarean Delivery: A Prospective Observational Study

Background and Objectives: The optimal prophylactic uterotonic strategy for high-risk elective cesarean delivery remains uncertain. We compared carbetocin and oxytocin in terms of additional uterotonic requirements and maternal outcomes. Materials and Methods: This prospective, single-center, nonrandomized observational study included 101 high-risk women undergoing elective cesarean delivery under spinal anesthesia. After cord clamping, 50 received carbetocin (100 μg IV) and 51 received oxytocin (10 IU IV followed by a 10 IU infusion). The primary outcome was additional intraoperative uterotonic use. Secondary outcomes included hemoglobin changes, hemorrhage-related interventions, physiological parameters, and adverse events. Results: Gestational age differed between groups (p = 0.042), with imbalances in some postpartum hemorrhage risk factors. Additional intraoperative uterotonic use was lower with carbetocin (24.0% vs. 47.1%; p = 0.016). After adjustment for gestational age, grand multiparity, and fetal macrosomia, oxytocin was associated with higher odds of additional uterotonic use (aOR = 2.4292; 95% CI 1.0147–5.9946; p = 0.0487). However, adjustment for the calendar date of surgery yielded a nonsignificant association (aOR = 2.34; 95% CI 0.97–5.82; p = 0.0615). No significant differences were detected in hemorrhage-related secondary outcomes or maternal adverse events. Group-by-time interactions were significant for heart rate and cumulative urine output. Heart rate was higher with carbetocin at 5 and 10 min and at uterine closure; model-estimated cumulative urine output at 2 h was 1.79-fold higher (95% CI 1.16–2.75; Bonferroni-adjusted p = 0.004). Conclusions: Carbetocin was associated with a lower requirement for additional intraoperative uterotonics under the regimens studied, but this finding is exploratory and does not establish causality. Larger randomized trials are needed.