Carbetocin vs. Oxytocin at Elective Cesarean Section

The study investigators are comparing 2 drugs (oxytocin and carbetocin) at 2 different dosages, to help prevent serious bleeding (hemorrhage) after cesarean deliveries. These drugs are used routinely to help contract the uterus and keep it contracted after the delivery of the baby and placenta; this reduces the amount of blood you might lose. At Mount Sinai Hospital, currently oxytocin is used, but its effect on the uterus is much shorter than that of carbetocin. Internationally, there is no consensus as to what the most effective drug to use is and at which dose. The Society of Obstetricians and Gynaecologists of Canada has recently revised its guidelines to suggest 100 micrograms (mcg) of carbetocin as the drug of choice at elective cesarean section. Guidelines from the United Kingdom and the United States currently suggest oxytocin at various doses as the drug of choice at elective cesarean sections. Previous studies at Mount Sinai Hospital have shown that lower doses of oxytocin, 0.35 International Units (IU), and carbetocin, 20 mcg, may be as effective as the higher recommended doses. The investigators plan to conduct a large study to confirm these findings so that they can use the most appropriate dose in the future. Furthermore, the investigators hope to demonstrate that side effects are lower with the lower dose regimens.