The effect of hyoscine N– butyl bromide on the duration of active phase of labor

Background and objective: Hyoscine N-butyl bromide acts by inhibiting cholinergic transmission in pelvic parasympathetic ganglia and antagonizing muscarinic receptors of smooth muscles in the abdomen and pelvic organs, thus relieving spasm aiding to cervical dilation. This study is to assess the efficacy of Hyoscine butyl bromide on cervical dilation in multigravid pregnant women during the active phase of labor. Methods: A randomized clinical prospective trial was conducted in maternity hospital in Sulaimaniyah, from 1 of January to the 1 of July 2010. Women were consecutively randomized into: the study group (A) who received 40 mg Hyoscine N-butyl bromide by slow intravenous injection in the active phase of first stage of labor and the control group (B) who received 2ml of normal saline. Each group consists of 130 patients after excluding high risk pregnancy. Results: Mean duration of active phase of labor was 142.69 min, 258.00 min in group A and B, respectively (p-value < 0 .001). Mode of delivery and neonatal outcome were comparable. No adverse maternal or fetal effects were noted. Conclusion: Intravenous Hyoscine N-Butyl Bromide shortens the duration of active phase of labor without any unwanted fetal or maternal effects, also it effectively shortens the 2 and 3 stages of labor.