Maternal glucose tolerance in pregnancy and child cognitive and behavioural problems in early and mid-childhood.

Background Maternal abnormal glucose tolerance during pregnancy may adversely affect offspring cognition and behaviour, but few prospective studies investigated this association at multiple points throughout childhood. Objectives We hypothesised that maternal abnormal glucose tolerance is associated with child cognitive and behavioural outcomes in early and mid-childhood. Methods We examined the associations of maternal abnormal glucose tolerance at 26-28 weeks of pregnancy with offspring cognitive and behavioural scores in 1421 children in the Project Viva pre-birth cohort. In early (mean 3.3 years) and mid-childhood (mean 7.9 years), we measured child cognition using validated instruments, the Kaufman Brief Intelligence Test, Wide Range Assessment of Memory and Learning, and the Wide Range Assessment of Visual Motor Abilities (WRAVMA); we assessed parent- and teacher-rated behavioural outcomes with the Strengths and Difficulties Questionnaire and the Behavioural Rating Inventory of Executive Function. We used linear regression models adjusted for potential confounders (maternal race/ethnicity, pre-pregnancy BMI, intelligence, age, parity, smoking status, education, and household income at enrolment, in addition to child's sex and age at assessment). Results Of 1421 mothers, 69 (4.9%) had gestational diabetes mellitus, 43 (3.0%) impaired glucose tolerance, 122 (8.6%) isolated hyperglycaemia, and 1187 (83.5%) normal glucose tolerance. Offspring born to women with gestational diabetes mellitus had lower total WRAVMA scores (-3.09 points; 95% CI -6.12, -0.05) in early childhood compared with offspring of women with normal glucose tolerance. None of the abnormal glucose tolerance categories during pregnancy were associated with any of the cognitive outcomes (verbal, non-verbal, and visual motor scores) or behavioural measures in mid-childhood. Conclusions Children born to mothers who had gestational diabetes mellitus had slightly lower scores on one cognitive test in early childhood. We found no evidence to support that maternal abnormal glucose tolerance was associated with cognitive or behavioural development in mid-childhood.