Randomized comparison of intravenous nitroglycerin and subcutaneous terbutaline for external cephalic version under tocolysis.

Objective: The purpose of this study was to compare the efficacy and safety of intravenous nitroglycerin with that of subcutaneous terbutaline as a tocolytic agent for external cephalic version at term.

Study Design: We performed a prospective randomized trial. Patients between 37 and 42 weeks of gestation were assigned randomly to receive either 200 microg of intravenous nitroglycerin therapy or 0.25 mg of subcutaneous terbutaline therapy for tocolysis during external cephalic version. The rate of successful external cephalic version and side effects were compared between groups.

Results: Of 59 randomly assigned patients, 30 patients received intravenous nitroglycerin, and 29 patients received subcutaneous terbutaline. The overall success rate of external cephalic version in the study was 39%. The rate of successful external cephalic version was significantly higher in the terbutaline group (55% vs 23%; P = .01). The incidence of palpitations was significantly higher in patients who received terbutaline therapy (17.2% vs 0%; P = .02), as was the mean maternal heart rate at multiple time periods.

Conclusion: Compared with intravenous nitroglycerin, subcutaneous terbutaline was associated with a significantly higher rate of successful external cephalic version at term.