The interval between a single course of antenatal steroids and delivery and its association with neonatal outcomes.

OBJECTIVE

This study was undertaken to determine whether the benefits of a single course of antenatal steroid treatment for neonatal respiratory morbidity diminish beyond 7 days.

STUDY

DESIGN

A retrospective chart review was performed of all deliveries less than 34 weeks' gestation where delivery occurred after completing a single course of antenatal steroids (dexamethasone or betamethasone). Maternal and neonatal charts were reviewed, treatment course was confirmed, and neonatal morbidities were collected.

RESULTS

Of 197 neonates whose mothers received a full course of antenatal steroids, 98 delivered within 7 days and 99 delivered more than 7 days after the initial dose. The 2 groups were similar in gestational age at delivery (30 weeks 0 days vs 30 weeks 4 days). The groups were also similar in maternal age, race, payor status, type of steroid given, route of delivery, gender, and birth weight. Overall, infants delivering within 7 days had a lower incidence of receiving respiratory support for more than 24 hours (62% vs 81%, P < .01), but there were no significant differences between the groups in surfactant treatment (39% vs 47%), use of mechanical ventilation (49% vs 59%), necrotizing enterocolitis (6% vs 4%), intraventricular hemorrhage (15% vs 20%), oxygen dependence at 28 days (24% vs 23%) or at 36 weeks estimated gestational age (13% vs 12%), length of stay (34 days vs 38 days), or mortality (2 vs 0). These results were no different when evaluating only infants delivered before 30 weeks.

CONCLUSION

Among infants exposed to a single course of antenatal steroids, delivering more than 7 days after initiation of treatment was associated with an increased need for short-term respiratory support, but not other measures of neonatal morbidity. These data challenge the concept of diminishing efficacy of steroids after 7 days, and question the need for considering a rescue course.