Outcomes in Early Adulthood for Individuals Born Very Preterm and/or with Very Low Birth Weight: Evidence from Multinational Cohorts

Background: Advances in neonatal care have improved survival rates for infants born very preterm (VP) and/or with very low birth weight (VLBW), yet their long-term outcomes into adulthood remain understudied. Objectives: To assess the impact of VP/VLBW status on mortality, educational attainment, and labor market outcomes in early adulthood using data from the RECAP Preterm Project. Methods: We used harmonized data from 5 nationally representative cohort studies in high-income countries (Canada, Germany, the Netherlands, New Zealand, and Norway) participating in the RECAP Preterm Project. Our sample included 2493 individuals born VP/VLBW and 496 control patients born at term. We used coarsened exact matching to compare adult outcomes between infants who were VP/VLBW and those born at term and an instrumental variable approach-using maternal nulliparity-to estimate the marginal effect of gestational age within the VP/VLBW group. Results: Mortality before adulthood was 16.7 percentage points greater among individuals who were VP/VLBW compared with control infants born at term (95% CI 13.2-20.2). Among survivors, the likelihood of attaining less than secondary education was 4.3 percentage points greater (95% CI -0.8 to 9.4). Differences in economic activity and working hours were small and uncertain. Within the VP/VLBW group, each additional week of gestational age was associated with a 6.8 percentage point reduction in mortality (95% CI -12.7 to -1.0), with weaker associations for educational and labor market outcomes. Conclusions: VP/VLBW birth is associated with elevated mortality and educational disadvantage in early adulthood. These findings highlight the importance of long-term support for this population beyond neonatal survival, particularly in education and development policy.