Uterine activity after betamethasone administration for the enhancement of fetal lung maturation

Objective: To assess the effect of steroids administered for the enhancement of fetal lung maturation on uterine activity. Design: A retrospective analysis. Setting: High-risk Pregnancy Unit, Golda Medical Center, Petah Tikvah, Israel. Patients: Fifty-nine courses of betamethasone therapy prescribed for various indications other than premature contractions were studied in 29 pregnant women at 26-34 weeks' gestation. Measurements: Uterine activity was monitored on the day of the first (but prior to) betamethasone injection, then daily for the next 3 consecutive days. The number of uterine contractions during the first 30 min of each tocodynamometric tracing was assessed. Results: The frequency of uterine activity after steroid administration is significantly higher in multiple pregnancies as compared to singletons, and significantly increases as the duration of pregnancy increases. However, labor was not induced and all women delivered at least 1 week after the last betamethasone injection. Conclusions: Since the increased uterine activity after administration of steroids for the enhancement of fetal lung maturation does not provoke labor, it is suggested that this increase in uterine activity seems to act as a temporary phenomenon. Therefore conservative management, rather than tocolysis, would seem appropriate.