OBJECTIVE: Our purpose was to prove our hypothesis that once preterm uterine contractions and/or labor is controlled with intravenous tocolysis, oral terbutaline, as a maintenance drug, does not prolong pregnancy. STUDY DESIGN: Before discharge, 184 patients between 24 and 35 completed weeks' gestation were prospectively randomized to continued bed rest either with or without oral terbutaline. Assignment was made with stratification into tour groups: group 1, those patients with a Bishop score greater than or equal to 5 with oral terbutaline (n = 50); group 2, those with a Bishop score greater than or equal to 5 without oral terbutaline (n = 53); group 3, those with a Bishop score <5 with oral terbutaline (n = 41); group 4, those with a Bishop score greater than or equal to 5 without oral terbutaline (n = 40). Oral terbutaline was discontinued at 37 completed weeks. RESULTS: No statistically significant differences were found in the number of readmissions, the number of unscheduled hospital visits, and the neonatal outcomes among the four groups. The gestational age at delivery and percent of deliveries at greater than or equal to 37 weeks were not significantly different when group 1 was compared with group 2 and group 3 was compared with group 4. CONCLUSION: Oral terbutaline maintenance does not improve pregnancy outcome in patients who have had initial successful intravenous tocolysis.