A systematic review and meta-analysis of randomized trials comparing carbetocin to oxytocin in prevention of postpartum hemorrhage after cesarean delivery in low-risk women.

Objectives: To evaluate the efficacy and safety of Carbetocin compared to oxytocin in prevention of postpartum hemorrhage (PPH) after low-risk cesarean delivery (CD).

Search Strategy: Screening of Medline, Web Of Science, Scopus, Google scholar, and clinical trials registry till January 2024 using the key words related to carbetocin, blood loss, PPH, Cesarean section and their MeSH terms was done.

Selection Criteria: This study included all RCTs conducted on women with low risk for developing PPH after CD and compared the administration of carbetocin to oxytocin without any language limitation. These studies compared carbetocin to oxytocin alone or oxytocin combined with misoprostol. The review included all doses and routes of carbetocin and oxytocin administration.

Data Collection And Analysis: The extracted data included study settings, the participants' size and characteristics, intervention details of both the study and control groups especially data about the dose route and timing of drug administration, the outcome parameters and trial registration details The reported outcomes included the requirement of additional uterotonic agents or blood transfusion, the difference between preoperative and postoperative hemoglobin, the occurrence of PPH, blood loss and drug adverse effects.

Main Results: Seventeen studies including 3667 participants were included. The need for additional uterotonic agents was evaluated in 14 studies with 3154 participants and revealed an OR of 0.53 with 95% CI of 0.39 and 0.72 (p < 0.001, I 41%). The incidence of PPH was reported in 11 studies with 2228 participants and revealed an Odd ratio of 1.08 with 95%CI of [0.81, 1.44] (p = 0.61, I 0%). The hemoglobin drop after the operation was evaluated in 3 studies with 1240 participants and revealed an MD of -0.08 with 95% CI of -0.10 and - 0.06 (p < 0.001, I 0%). The need for blood transfusion was evaluated in 9 studies with 1936 participants and revealed an OR of 0.57 with 95% CI of 0.34 and 0.97 (p = 0.04, I 0%).

Conclusion: Carbetocin administration during CD in women with low risk for PPH is associated with less need for additional uterotonic agents (moderate evidence), less need for blood transfusion (high evidence) and lower hemoglobin drop (high evidence) when compared to those who underwent oxytocin administration without an increase in adverse effects.