Neurodevelopmental outcomes at age 3 years of preterm infants born at 22-31 weeks' gestation.

Objective: To evaluate neurodevelopmental outcomes of very preterm infants by gestational age (GA) using high follow-up rate data.

Methods: This secondary analysis included infants born before 32 weeks' gestation in 2012-2014 from the Improvement of NICU practices and Team Approach Cluster randomized controlled Trial (INTACT). The primary outcome was survival without moderate or severe neurodevelopmental impairment (NDI).

Results: Among 2722 infants, NICU survival rate was 96.5%, ranging 72.1-99.6% at 22-31 weeks. At age three years, 2336 (89.5% of 2610 survivors) were completely assessed; 303 had moderate NDI and 183 had severe NDI. Of these, the proportions of infants surviving without NDI increased with GA; 45.2% at 22 weeks, 57.5% at 23 weeks, 88.1% at 31 weeks.

Conclusions: Although survival without NDI varied by GA, more than half (55.0%, 83/151) of infants born at 22-23 weeks who survived to age three years were without neurodevelopmental sequelae.