BackgroundSocioeconomic factors influence language development in the general population, but the association remains poorly documented in children born very preterm (VPT). We assessed the impact of maternal education on language development in children born VPT and effect modification by perinatal risk.MethodsData were from the Effective Perinatal Intensive Care in Europe (EPICE) population-based cohort of children born <32 weeks’ gestational age (GA) in 2011/2012. Regions from six countries (Estonia, France, Germany, Italy, Sweden and UK) used a validated short form MacArthur Developmental Communicative Inventories Checklist to assess language at 2 years corrected age. Perinatal variables were collected from clinical records. We assessed expressive language delay (ELD), defined as (a) not combining words; and (b) expressive vocabulary <10th percentile of norms for age and sex. Perinatal risk (low, moderate and high) was determined using GA, small for GA and neonatal morbidities. We estimated adjusted risk ratios (aRR) of ELD by maternal education with inverse weighting to account for non-response bias.ResultsOf 2741 children, 24.6% were not combining words and 39.7% had a low expressive vocabulary. Low maternal education (lower secondary or less compared with a bachelor’s degree or more) increased risks of ELD: not combining words: aRR=1.52 (95% CI 1.36 to 1.69); low expressive vocabulary: aRR=1.25 (1.04 to 1.51). For children with low perinatal risk, the aRR were 1.88 (1.26 to 2.80) and 1.44 (1.06 to 1.95), respectively, compared with those with high perinatal risks: 1.36 (1.10 to 1.67) and 1.11 (0.97 to 1.27), respectively.ConclusionLow maternal education affects ELD for children born VPT, although the association appears attenuated among those with highest perinatal risk.