The purpose of this study was to investigate the effects of Pethedine on maternal outcome of labor in nulli-parous women. In a randomized clinical trail 90 nulli-parous women with uncomplicated singleton pregnancies at term were randomly assigned into two groups. The first group received 50 mg Intra Muscular Pethidine and the second group received an equal volume Intravenous Normal Saline as Placebo throughout active labor. Duration of active phase and second stage of labor were shorter in Pethidine group in compared to Normal Saline group, but not for the third stage. Pethidine reduced the need to labor augmentation. Maternal nausea and vomiting were similar between groups. Pethedine significantly decreased the duration of active labor and reduced the frequency of both Cesarean Section and Oxytocin administration in nulli-parous women.
