Effectiveness of Oral Maintenance Terbutaline Therapy after Threatened Preterm Labor

Abstract

The purpose of this study was to compare the effectiveness of oral maintenance terbutaline with no therapy after successful intravenous tocolysis in reducing the rate of preterm labor and identify predictors of preterm labor. A historical cohort study was conducted in 91 pregnant women with 28 to 35 weeks’ gestation who were admitted with threatened preterm labor. After successful treatment with intravenous terbutaline sulfate, 46 patients participated to receive oral maintenance terbutaline therapy and 45 patients received no therapy. The dose of terbutaline was given orally 2.5 mg every 6 hour and was continued until the 36 weeks of completed gestation. There was no significantly different between oral terbutaline and no therapy groups with respect to term delivery (76.09% vs 66.67%, p=0.32), incidence of recurrent preterm labor (26.09% vs 31.11%, p=0.60), time gained (31.33 ± 16.92 vs 28.11 ± 14.96 days, p=0.34) and neonatal outcome. Kaplan-Meier and log-rank test revealed that survival time to term delivery was not significant difference between two groups (p=0.34). Adverse effects during oral terbutaline treatment were palpitation and fetal tachycardia. Logistic regression indicated that only recurrent preterm labor was a significant predictor of preterm labor. Oral maintenance terbutaline therapy after successful parenteral tocolysis appeared to be ineffective tocolytic agent for pregnancy prolongation or a reduction in the incidence of recurrent preterm labor in women with 28 to 35 weeks’ gestation.