Prevention of prolonged labor by active management of first stage using spasmolytic drugs a double blind randomized controlled clinical study

Background: Dystocia remains the most common indication for emergency cesarean section especially for primigravidae. As such, it is a major contributor to operative and instrumental intervention. Type of Study: A double-blind, randomized, controlled clinical trial. Objective: This study aimed to evaluate the effect of 2 spasmolytic drugs, Drotaverine and Hyoscine-N-Butylbromide on shortening of first stage of labor. Setting: Obstetrics and Gynecology Departments of Al-Azhar university hospital (Assiut), Egypt. Patients & Methds: 150 full term primigravidae in labor (cervical dilatation 3-4cm with regular progressive uterine contractions 3-4/ 10 minutes, each lasting for at least 40 seconds) were recruited for this study during the period from June 2018 to december 2018. Patients were divided into three equal groups (50 patients for each). Group I: Received (40mg) drotaverine hydrochloride by slowly IV infusion. Group II: Received (20mg) hyoscine-n-butylbromide by slowly IV infusion. Group III: (control): Received Sterile water for injection (placebo). Results: the rate of cervical dilation was significantly higher in group 1&II compared to the control group; also duration of 1st stages was significantly shorter in the same groups while no significant difference in duration of 2nd stage were present among the 3 groups, the degree of severe pain and the need for oxytocin augmentation doses were significantly lesser in both groups compared to control (p<0.001). The neonatal outcomes in the form of APGAR score was higher and need for NICU admission was significantly lower in group I&II compared to group III. Conclusion: both drugs used in this study have significant effects on shortening of 1st stage of labor with lesser units of oxytocin needed for augmentation with good analgesic effect and good neonatal outcome, however, Drotaverine hydrochloride was better as it was more effective beside it has the strongest labor pain relieve and lesser maternal adverse effects. Recommendations: We recommend using of either drug in enhancing first stage of labor however; Drotaverine hydrochloride is preferable as it is more effective with minimal maternal adverse effects.