Side-effects of intravenously versus intramuscularly oxytocin for postpartum hemorrhage: a systematic review and meta-analysis of randomized controlled trials

Background: Oxytocin is the gold standard uterotonic agent for prevention of postpartum hemorrhage. However, there is no consensus with clear evidence about the side-effects of oxytocin administered intravenously or intramuscularly for management of the third stage of labor. We conducted a systematic review and meta-analysis of randomized controlled trials to evaluate the side-effects of intravenously or intramuscularly oxytocin for preventing postpartum hemorrhage in the third stage of labor.Methods: Six representative databases were searched from the inception to July 2023. Randomized controlled trials which explored the intravenously and intramuscularly oxytocin and provided at least one side-effect were included. Statistical analysis included random or fixed-effect meta-analyses using relative risk.Results: Nine studies included, involving 8,295 participants. Ten types of side-effects were reported. There was no statistical difference in hypotension (RR = 1.01, 95%CI = 0.88-1.15), anemia (0.98, 0.83-1.15), tachycardia (0.90, 0.69-1.17), shivering (0.90, 0.69-1.17), headache (0.86, 0.31-2.37), nausea (0.70, 0.20-2.42), vomiting (0.97, 0.26-3.58), uvular edema (0.82, 0.23-2.91), diarrhea (0.97, 0.26-3.58), and fever (0.97, 0.26-3.58) between intravenously or intramuscularly groups.Conclusion: There are no significant differences of side-effects between intravenously and intramuscularly administration of oxytocin for preventing postpartum hemorrhage in the third labor.