Neurodevelopmental Outcomes of Extremely Preterm Infants at Two Years Corrected Age

Abstract

Extremely preterm birth, before 28 completed weeks of gestation, remains the leading contributor to early childhood neurodevelopmental impairment among survivors of neonatal intensive care, and two years corrected age has become the field's standard timepoint for a first formal assessment of cognitive, language, and motor outcome. This article synthesizes the literature on neurodevelopmental outcomes at this timepoint, drawing on the major international cohort studies -- EPICure, EPIPAGE-2, the Swedish EXPRESS study, and the Dutch EPI-DAF study among others -- that have defined the field's empirical baseline, alongside the assessment-instrument literature, the neonatal brain-injury literature, and the intervention trials with the clearest evidence of shifting two-year outcome. A recurring and troubling finding across these cohorts is that survival at the most immature gestations has improved substantially over the past three decades while the proportion of survivors with severe disability has, on the best available like-for-like evidence, remained largely unchanged. We give particular weight to how much of the reported variation in outcome rates across cohorts and calendar time reflects genuine clinical change versus changes in the assessment instruments themselves, to the prognostic gradient carried by intraventricular hemorrhage severity, and to the small number of interventions, chiefly antenatal magnesium sulfate and postnatal caffeine, with randomized evidence of a genuine two-year benefit. Read together, the evidence supports two-year assessment as a genuinely informative but non-final snapshot, leaving the disconnect between improving survival and stagnant severe-disability rates as the field's most pressing open question.