Preterm birth and expressive language development across the first 5 years of life: A nationally-representative longitudinal path analysis

Multiple factors including the child's non-linguistic characteristics and caregiving environment can affect language development. Since preterm birth (<37 weeks' gestation) can negatively affect language development, this study used path analysis to investigate whether the influence of preterm birth on expressive language development at 3 and 5 years of age is mediated by a child's non-linguistic characteristics (temperament and cognitive, motor, and social-personal abilities), caregiving environment (maternal and paternal stress and depression, mother-child and father-child relationship quality), and interactions between these domains. These analyses were conducted using three waves of data (ages: 9 months, 3 years, 5 years) on 8,712 children (4,300 female; 535 preterm) from a nationally-representative longitudinal study in Ireland. Preterm birth was indirectly (but not directly) associated with expressive language at 3 years of age via cognitive and social-personal abilities (but not motor abilities, mother-child relationship quality, or father-child relationship quality) at 9 months. There was no direct or indirect effect of preterm birth on expressive language at 5 years of age. Preterm birth negatively affected mother-child and father-child relationship quality at 3 years via fussy-difficult temperament and mother's/father's stress (but not depression) at 9 months. These findings are discussed with reference to international standards for neonatal care, including the need for long-term developmental monitoring of children born preterm by multidisciplinary healthcare teams, alongside parental supports promoting mental health and confidence in caregiving tasks. Future study recommendations are made to expand the tested models in line with family systems perspectives.