Background: Preterm birth is the single most important determinant of adverse infant outcome. Tocolytic therapy has shown beneficial effect in certain selected patients. The present study was conducted to evaluate the efficacy, maternal and fetal outcome with the use of Transdermal Glyceryl nitrate patches versus Intravenous Ritodrine tocolytic agents.
Methods: Study included 50 patients of gestation 24-34 weeks in preterm labor. Group I: Glyceryl trinitrate patch releasing 10mg/24 hours (0.4mg/ hour) was applied transdermally and repeated after 2 hours if no reduction in contractions was seen. Group II: Intravenous Ritodrine infusion prepared by adding 50mg to a bottle of 5% dextrose or ringer lactate solution and infusion started at an initial rate of 0.05mg/min which was increased by 50 micrograms per minute every 15 min until contractions ceased.
Results: 22 patients in group I treated with GTN and 19 patients in group II treated with Ritodrine achieved successful tocolysis. The difference was statistically insignificant (P value - 0.23). Mean Gestational age at delivery was 34.97 in GTN Group as compared to 33.24 weeks in Ritodrine Group ; difference which is statistically significant (P = 0.0004). Very few adverse effects were observed in the GTN Group. Comparatively, the Ritodrine Group had severe adverse effects requiring discontinuation of therapy. Fetal outcome was satisfactory in both groups.
Conclusions: The effects of Glyceryl trinitrate and Ritodrine in the treatment of preterm labor were essentially similar. Glyceryl trinitrate is associated with lesser maternal and fetal adverse effects and appears to be a very viable, inexpensive and safer alternative to Ritodrine.
GTN Patch, IV Ritodrine, Preterm labour, Tocolysis