Cognitive and Educational Outcomes After Preterm Birth or Low Birth Weight: An Umbrella Review and Meta-Analysis.

IMPORTANCE: Advances in perinatal care have improved survival for infants born preterm (<37 weeks' gestation) or with low birth weight (<2500 g), but these individuals remain at increased risk of poorer cognitive and educational outcomes. OBJECTIVE: To synthesize evidence from systematic reviews on both cognitive and educational outcomes in individuals after preterm birth or with low birth weight using an umbrella review and meta-analysis approach. DATA SOURCES AND STUDY SELECTION: The PubMed, Embase, ERIC, RePEc, EconLit, and Google Scholar databases were searched from inception through April 2025 for systematic reviews examining associations between preterm birth or low birth weight and cognitive or educational outcomes. DATA EXTRACTION AND SYNTHESIS: Two reviewers independently selected studies, extracted data, and evaluated study quality and risk of bias (following the guidelines from the Joanna Briggs Institute). The effect sizes from the original primary studies included in meta-analyses were reanalyzed and converted to equivalent Hedges g effect sizes. Data were pooled using random-effects models. The subgroup analyses examined associations by gestational age, birth weight, and age. Narrative synthesis supplemented quantitative findings. MAIN OUTCOMES AND MEASURES: General cognitive ability (intelligence quotient [IQ]) and 4 domains of educational outcomes (academic attainment, type and length of schooling, need for additional educational support, and educational costs). RESULTS: Forty systematic reviews (22 with meta-analyses and 18 with narrative syntheses) were included, yielding 788 reanalyzed effect estimates. Preterm birth or low birth weight was associated with lower IQ (Hedges g, -0.65 [95% CI, -0.69 to -0.61]), poorer attainment in reading (Hedges g, -0.65 [95% CI, -0.87 to -0.43]), lower performance in mathematics (Hedges g, -0.77 [95% CI, -1.03 to -0.50]), lower performance in spelling (Hedges g, -0.56 [95% CI, -0.65 to -0.46]), and greater need for special educational support (Hedges g, 0.58 [95% CI, 0.41 to 0.74]). The associations were stronger at earlier gestational ages and lower birth weights, appeared to attenuate during adolescence, and remained evident into adulthood. Evidence on schooling and educational costs was limited but suggested lower school completion rates and higher educational costs. CONCLUSIONS AND RELEVANCE: This umbrella review and meta-analysis found that preterm birth and low birth weight were associated with persistent cognitive and educational disadvantages across the life course, underscoring the importance of early identification and long-term monitoring to inform health and educational planning.