Trends in Morbidities of Late Preterm Infants in the Neonatal Intensive Care Unit

Abstract Objective To characterize demographics and trends in length of stay (LOS), morbidities, and mortality in late preterm infants. Study design Cohort study of infants born between 34 0/7 and 36 6/7 weeks gestation between 1999 and 2018 without major congenital anomalies at Pediatrix Medical Group neonatal intensive care units (NICUs). Results 307 967 infants from 410 NICUs met inclusion criteria. The median (25th -75th percentile) LOS was 11 (8–16) days in the entire period. Postmenstrual age (PMA) at discharge increased over time for all gestational ages (p < 0.001). There was a decrease in invasive ventilation, receipt of phototherapy, and reflux medications observed (p < 0.001). Conclusion In this large cohort, late preterm infants had an increased PMA at discharge and no significant improvement in LOS during the study period. Multiple practice changes were observed. There continue to be opportunities to improve morbidities among late preterm infants and to potentially decrease hospital stays.