Association of tocolytic therapy with antenatal steroid administration and infant outcomes. Newborn Lung Project.

The use of tocolytic agents to halt premature labor is controversial. We examine a database on very low-birth-weight infants born following the onset of premature labor (n = 540) for association between tocolytic and antenatal steroid therapy, and to assess neonatal and childhood outcomes following combined therapy. Data are from a multicenter regionally based study of all infants below 1501 g at seven neonatal intensive care units (NICUs) in Wisconsin and Iowa, born August 1, 1988 through June 30, 1991. Infant outcomes analyzed are death in the first 30 days, respiratory distress syndrome (RDS), and intraventricular hemorrhage (IVH). Fewer deliveries occurred within 12 hours of labor onset with tocolytics (61 vs. 75% without). A strong association between tocolytic therapy and antenatal steroid administration was found [adjusted odds ratio OR = 5.7, 95% confidence interval CI: (3.3, 10.0)]. Tocolytics were associated with lower mortality in the first 30 days [OR = 0.29, CI: (0.15, 0.56)]. Joint administration of tocolytics and antenatal steroids versus neither was associated with lower incidence of the combined outcome of respiratory distress syndrome (RDS) or death [OR = .30, CI: (0.15, 0.60)] and grade III-IV IVH or death [OR = 0.35, CI: (0.14, 0.98)]. Tocolytic therapy alone was not associated with IVH grade III-IV [OR = 1.0, CI: (0.57, 1.9)] among survivors.