Outcomes in Early Adulthood for Very Preterm and Very Low Birth Weight Individuals: Evidence from Multi-National Cohorts

Background. Advances in neonatal care have improved survival rates for very preterm (VP) and very low birth weight (VLBW) infants, yet their long-term outcomes into adulthood remain understudied. Objectives. To assess the impact of VP/VLBW status on mortality, educational attainment, and labour market outcomes in early adulthood using data from the RECAP Preterm Project. Methods. We used harmonised data from five 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 2,493 individuals born VP/VLBW and 496 term-born controls. We employed coarsened exact matching (CEM) to compare adult outcomes between VP/VLBW and term-born individuals, and an instrumental variable (IV) 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 higher among VP/VLBW individuals compared to term-born controls (95% CI: 13.2, 20.2). Among survivors, the likelihood of attaining less than secondary education was 4.3 percentage points higher (95% CI: −0.8, 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, −1.0), with weaker associations for educational and labour 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.