Respiratory Compliance in Late Preterm Infants (34 ^0/7 -34 ^6/7 Weeks) after Antenatal Steroid Therapy

Objective: To compare respiratory compliance in late preterm infants (34 ^0/7 -34 ^6/7 weeks) who received antenatal steroids vs matched late preterm infants who did not receive antenatal steroids. Study design: This was a single-center prospective cohort study. Patients were matched for birth weight, gestational age, race, and sex. Respiratory compliance was the primary outcome measured with the single breath occlusion technique. Results: We studied 25 late preterm infants treated with antenatal steroids and 25 matched infants who did not receive antenatal steroids. The treated infants had a significantly increased respiratory compliance/kg (adjusted 95% CI 0.05, 0.49; P =.016) and fewer required continuous positive airway pressure (P =.007) or >24 hours of supplemental oxygen (P =.046). There was no difference in surfactant therapy. Conclusions: Respiratory compliance was significantly increased in this cohort of late preterm infants born at 34 ^0/7 -34 ^6/7 weeks who received antenatal steroids compared with matched infants who did not receive antenatal steroids. Although not randomized, these data provide physiologic support for the possible beneficial effects of antenatal steroids in late preterm infants.