The combined influence of parental education and preterm birth on school performance.

BACKGROUND: Social background and birth characteristics are generally found to be independently associated with school achievements but the underlying mechanisms are not fully understood. This study aimed to explore how parental education and shorter gestational age jointly influence school performance in a cohort of Swedish children. METHODS: 10,835 children born between 1973 and 1981 were studied, the third generation of the register-based Uppsala Multigenerational Birth Cohort. Ordinal logistic regression models were fitted to estimate OR of achieving middle and high grades in Swedish language at age 16 years, relative to low grade, by parental education and own gestational age, adjusting for potential confounders. RESULTS: In children from families with lower parental education, the adjusted OR of receiving a higher grade was 0.54 (95% CI 0.41 to 0.71) for preterm (