This is a prospective controlled randomized trial conducted in 92 women with singleton pregnancies in preterm labor. The tocolytic efficacy and safety of combination atosiban and nifedipine was compared with that of the single agent, atosiban. Both lines of intervention was administered for 48 hours. Progression of labor was assessed by the frequency of uterine contractions and cervical changes. For statistical purpose, intent-to-treat (ITT) analysis was used throughout. Efficacy, as determined by the proportion of women in each group who did not deliver after therapy initiation, was comparable with no significant differences, at 48 hrs (91.5% vs. 91.1%) and at 7 days (90.7% vs. 85.7%) for the atosiban and the combination groups respectively. Safety was assessed by the numbers of adverse events. Maternal side effects were reported more in the combination group (34% vs. 64%; P = 0.006). Perinatal outcomes were similar between the groups. We conclude that the addition of nifedipine did not substantially improve the clinical outcomes beyond that were achieved with atosiban alone. Moreover, it has increased maternal side effects. Future research could focus on combination of other tocolytics.