Effect of Melatonin on Blood Loss After Cesarean Section: A Prospective Randomized Double-Blind Trial.

BACKGROUND AND OBJECTIVES

The similarities between the melatonin and oxytocin signaling could lead to increased contractility of myometrium. We designed this randomized double-blind, placebo-controlled trial to evaluate the efficacy of melatonin in reduction of blood loss during and after the lower segment cesarean section.

METHODS

One hundred and twenty patients who had been scheduled for cesarean section under spinal anesthesia were enrolled in the study. We randomly allocated them to one of the three following groups to receive either melatonin 3 mg (M), melatonin 6 mg (M), or placebo (P) sublingually 20 min before the surgery. The hemoglobin levels before and 12 h after surgery, the mean weight of the materials used in the operation time, the need for additional oxytocic therapy, and the incidence of adverse effects were probed and recorded.

RESULTS

There was a significant difference between the group M and both M and P in the mean weight of the materials ( = .024 and .041, respectively) and between M and P groups in terms of mean decrease in hemoglobin during 12 h after cesarean section ( = .029).

CONCLUSION

Using 6 mg melatonin, sublingually, as a premedication in patients undergoing cesarean section with spinal anesthesia could statistically reduce the amount of blood loss after the lower segment cesarean section, although it may not be clinically meaningful.: ACTRN12612000117819 and : NCT01572805.