Double-blind randomized controlled trial comparing the effect of carbetocin and oxytocin for the prevention of postpartum hemorrhage among high risk women following vaginal delivery.

PURPOSE: The objective of this study was to compare the efficacy and safety of carbetocin, a long oxytocin analogue, with oxytocin in preventing postpartum hemorrhage.

METHODS: Sixty women eligible for the study were enrolled on this prospective, double-blinded randomized controlled trial. They were randomized to receive either a single dose of 100-microgram intravenous carbetocin or oxytocin infusion (a mixture of 10 IU oxytocin and 1 liter of D5 containing intravenous fluid) upon delivery of the anterior shoulder of the baby. The primary outcome measure was a difference in hemoglobin drop measure 242 hours postpartum.

RESULTS: A significant drop of hemoglobin level 24 hours  postpartum was observed in the oxytocin group (-1.1) compared to the carbetocin (-0.6). The incidence of additional uterotonic agents and average estimated blood loss were lower with carbetocin. Uterine massage was needed in almost all patients who received oxytocin compared to a negligible number of those in the carbetocin group. Blood pressure and pulse rate of the patients were logged though no statistical difference was observed. The onset and duration of action was rapid and longer, respectively with carbetocin. There was no difference in the incidence of side effects between the two groups.

CONCLUSION: Carbetocin appears to be more effective than a continuous infusion of oxytocin with similar safety profile, thus a good alternative to conventional  uterotonic agents.