Introduction: Labour is a physiological process characterized by onset of uterine contractions leading to progressive increase in frequency, intensity and duration of uterine contractions, effacement and dilatation of cervix with descent of foetus through birth canal resulting in delivery of foetus with placenta and membranes. Hyoscine butyl bromide is most commonly used in labour room and has variable results in both primigravida and multigravida. Aim and Objective: 1. To evaluate the efficacy of Hyoscine-n-butyl bromide (buscopan) suppository in the active phase of labour in a primigravida.2. To evaluate the maternal and fetal complications of using the buscopan suppository. Materials and Methodology: Primigravida with gestational age 37 completed weeks-40 weeks admitted in the labour ward with spontaneous onset of labour or induced labour who-fulfil the inclusion & exclusion criteria were randomly selected in this study after taking informed consent. Study group: 150 pregnant women at the initiation of active phase allowed forlabour with instillation of single dose of Buscopan rectal suppository (10 mg) in active phase for cervical dilatation. Control group: 150 pregnant women at the initiation of active phase allowed forlabour without any drug for cervical dilatation. Study Design: Prospective case control study. Result: The mean duration of active phase of labour in study group is 3 hours 10 minutes & in control 5 hours 44 minutes. The difference between both the groups was statistically significant ('p' value < 0.001). No significant difference in maternal and fetal complications between study group and control group. Conclusion: Buscopan suppository was very effective in reducing the duration of active phase of labour by promoting cervical dilatation. There was no significant second or third stage complication with the use of the drug. No untoward side effects were noted in the mother or foetus.