Maternal and fetal side effects of tocolysis using transdermal nitroglycerin or intravenous fenoterol combined with magnesium sulfate.

OBJECTIVE

To compare the maternal and fetal side effects of transdermal nitroglycerin and intravenous fenoterol combined with magnesium sulfate in a prospective randomised study.

STUDY

DESIGN

Fifty pregnant women between 27 and 35 weeks of gestation with preterm labour were treated with either nitroglycerin (0.4-0.8 mg/h) or fenoterol (60 - 120 microg/h). Outcome parameters were (1) the effects on fetal and maternal heart frequency (FHF/MHF) and blood pressure, and (2) subjective experiences of adverse effects assessed by utilising a questionnaire.

RESULTS

In the fenoterol group, elevated mean MHF, FHF and systolic blood pressure were recorded compared to nitroglycerin. Fewer maternal side effects were reported in the nitroglycerin group. Palpitations (82%), tremor (68%) and restlessness (64%) were most common in the fenoterol group (two drop-outs), whereas nitroglycerin caused headaches in 71% of the cases (four drop-outs).

CONCLUSION

Transdermal nitroglycerin appears to be a safe therapy for the mother and fetus and is a promising new option for the treatment of preterm labour.