Neurodevelopmental Outcomes of Moderate-to-Late Preterm Infants

Purpose: Preterm infants are known to be at a risk of neurodevelopmental delay; however, limited data are available on the outcomes of moderate-to-late preterm (MLPT) infants (born at 32 to 36 weeks’ gestation). The Korean Developmental Screen ing Test (K-DST) for infants and children is a recently designed screening test for Korean infants and children. The current study aimed to evaluate the neurodevelopmental outcomes of MLPT infants and investigate the risk factors associated with neurodevelopmental delay. Methods: A total of 119 MLPT infants admitted to a neonatal intensive care unit (NICU) of a tertiary hospital in Korea were enrolled. The infants were assessed during two follow-up periods (first: 16 to 24 months of corrected age; second: 24 to 41 months of corrected age). The perinatal factors in the NICU that were associated with delayed development were analyzed. Results: In all sections of the K-DST, the proportion of infants with developmental delay was higher in the second period (5.6% to 9.3%) than in the first period (0.9% to 5.4%). A total of 10% to 17% of the infants presented with persistent delay throughout the two periods based on five sections of the K-DST. Male sex, oxygen therapy duration, and younger maternal age were the risk factors affecting at least one section during the second period. Conclusion: MLPT infants showed greater developmental delay than the general infant population. Considering that early intervention is important for good longterm outcomes, close observation of male MLPT infants and MLPT infants who received oxygen therapy is warranted.