H. Yanny et al., Double-blind randomised controlled trial of glyceryl trinitrate spray for external cephalic version, BR J OBST G, 107(4), 2000, pp. 562-564
A placebo controlled trial of glyceryl trinitrate was carried out in women
whose first attempt at external cephalic version without tocolysis had been
unsuccessful. No significant differences between groups were found and no
side effects were noted. It is recommended that a larger, possibly multicen
tre study, should be undertaken.