Authors: Binyamin Y et al.
International Journal of Obstetric Anesthesia Vol 66 May 2026
This single-center, retrospective before-and-after cohort study compared routine prophylactic carbetocin with oxytocin for prevention of uterine atony during cesarean delivery.
Study Design
All consecutive cesarean deliveries over 2 matched 3-month periods were included:
• February–April 2022: Oxytocin group
3–5 IU IV bolus + 20 IU in 1000 mL over 3 hours
• February–April 2023: Carbetocin group
100 µg IV bolus
Total analyzed cases: 1,349
• Oxytocin: 659
• Carbetocin: 690
Primary Outcome
Need for additional uterotonics.
Secondary Outcomes
• Postoperative hemoglobin change (within 24 ± 6 hours)
• Packed red blood cell transfusion
• ICU admission
• Relaparotomy
• Length of stay
Key Findings
-
Additional uterotonics
32.2% in oxytocin group vs 20.4% in carbetocin group (P < 0.001)
Adjusted analysis:
Carbetocin associated with significantly lower odds of additional uterotonics
OR 0.53 (95% CI 0.41–0.68; P < 0.001)
-
Hemoglobin drop
Median decrease:
• Oxytocin: 1.2 g/dL
• Carbetocin: 1.0 g/dL
Statistically significant but small absolute difference (0.2 g/dL). -
Blood transfusion
4.2% oxytocin vs 2.2% carbetocin (P = 0.030) -
Other outcomes
Carbetocin group had shorter hospital stays; ICU admission and relaparotomy were rare and not major drivers of difference.
Interpretation
Carbetocin, a long-acting oxytocin analog, provides sustained uterotonic effect after a single bolus. In this real-world cohort, its use was associated with:
• Reduced need for rescue uterotonics
• Modestly less postoperative hemoglobin decline
• Lower transfusion rates
The transfusion reduction (absolute difference 2%) may be clinically meaningful at scale in high-volume obstetric units.
However, limitations are important:
• Before-and-after design
• Potential unmeasured confounders
• Practice evolution between 2022 and 2023
• Single-center setting
Thus, associations are robust but not definitively causal.
Clinical Implications
For cesarean delivery, particularly in high-risk PPH settings:
• A single 100 µg bolus of carbetocin simplifies workflow.
• Reduced need for additional uterotonics may decrease polypharmacy and hemodynamic instability.
• Potential system efficiencies (no infusion needed).
Cost and formulary considerations remain relevant, as carbetocin is typically more expensive than oxytocin.
Key Points
• Carbetocin reduced additional uterotonic use (20% vs 32%).
• Lower transfusion rate observed (2.2% vs 4.2%).
• Hemoglobin drop slightly smaller with carbetocin.
• Before-and-after design limits causal inference.
• Supports carbetocin as effective prophylaxis during cesarean delivery.
For obstetric anesthesia services, this study adds real-world data supporting carbetocin as a pragmatic alternative when sustained uterotonic effect from a single bolus is desirable.
Thank you International Journal of Obstetric Anesthesia for sharing this study.