A randomized controlled trial to study the effect of IV hydration on the duration of labor in nulliparous women.

PURPOSE: To compare the effects of two different regimens of intravenous hydration and oral hydration on the duration of active labor.

METHODS: Two hundred and ninety-three low risk term primigravida in active labor were randomized into three groups. The first group had 99 patients who received oral fluids only, the second group of 98 patients received intravenous Ringer lactate at the rate of 125 ml/h (IV 125 ml) and the third group had 96 patients who received intravenous Ringer lactate at a rate of 250 ml/h (IV 250 ml). Amniotomy and oxytocin administration were allowed according to the physician's discretion.

RESULTS: The mean duration of labor in the oral fluid group was 391, 363 min in the 125 ml/h group and 343 min in the 250 ml/h group, P = 0.203. The incidence of prolonged labor more than 12 h in the oral fluid group was 7.1% in the oral fluid group, 4.1% in the 125 ml/h group and 3.1% in the 250 ml/h group, P = 0.402. The oxytocin requirement was 37% in the oral group, 32% in the 125 ml/h group and 33% in the 250 ml/h group, P = 0.68. There was a statistically significant reduction in the incidence of vomiting in patients receiving intravenous hydration, i.e. 24.2% in the oral group, 11.2% in the 125 ml/h group and 6.3% in the 250 ml/h group, P = 0.001. There was no difference in the mode of delivery, maternal or neonatal complications between the three groups.

CONCLUSION: This study establishes a trend towards decreased incidence of prolonged labor and less vomiting in patients receiving intravenous hydration.