Variations in survival outcomes of infants born at 22–23 weeks’ gestation by neonatal intensive care quality level in Korea

Abstract

Survival outcomes for infants born at 22–23 weeks’ gestation vary widely across neonatal units. This national, prospective cohort study evaluated 919 infants born at 22–23 weeks’ gestation in South Korea between 2013 and 2022, using Korean Neonatal Network data. Infants were categorized based on the level of neonatal care: 785 in lower-level centers (Group A) and 134 in higher-level centers (Group B). Survival was significantly higher in Group B (64.9%) compared to Group A (29.3%) (P < 0.0001). Early deaths occurred more frequently and earlier in Group A. Proactive care—including antenatal corticosteroids, antenatal antibiotics, and immediate surfactant administration—was more common in Group B. Antenatal corticosteroid was significantly associated with reduced risk of death (hazard ratio 0.58; 95% confidence interval, 0.49–0.69; P < 0.0001). The timing of rapid decline in survival was delayed in higher-level centers. In addition, classifying institutions into higher- and lower-level groups according to the survival of infants born at 22–23 weeks’ gestation (≥50% vs. <50%) provides a good reflection of the quality of neonatal care. These findings highlight the importance of proactive care and timely in utero transfer to higher-level units in improving survival for peri-viable infants. © The Author(s) 2026.