Maternal high body mass index, but not gestational diabetes, is associated with poorer educational attainment in mid-childhood.

Background: Previous studies suggest that gestational diabetes mellitus is associated with poorer cognitive outcomes in children. However, confounding factors, especially maternal body mass index, have been poorly accounted for.

Objective: This study aimed to examine the independent associations between maternal body mass index, gestational diabetes mellitus status, and educational outcomes.

Study Design: Antenatal data from a prospective birth cohort (Pregnancy Outcome Prediction Study, 2008-2012, Cambridge, United Kingdom) were linked to mid-childhood educational outcomes (Department for Education, United Kingdom). A total of 3249 children born at term were stratified by maternal gestational diabetes mellitus status and body mass index at booking (<25 vs ≥25 kg/m). Regression models adjusted for relevant maternal, child, and socioeconomic factors were used to determine associations with academic outcomes at ages of 5 to 7 years.

Results: No differences in educational attainment were found between children exposed to gestational diabetes mellitus and nonexposed children. Neither maternal glucose levels measured at 11 to 14 or 24 to 28 weeks, nor acceleration of the fetal abdominal circumference growth velocity were related to educational attainment at ages of 5 to 7 years. Children of mothers with booking body mass index ≥25 kg/m (vs <25 kg/m) were ∼50% more likely to not meet expected educational standards regardless of gestational diabetes mellitus status (age 5: adjusted odds ratio, 1.44; 95% confidence interval, 1.19-1.74; P<.001; age 6: adjusted odds ratio, 1.61; 95% confidence interval, 1.28-2.02; P<.001). The association between maternal body mass index and offspring educational attainment is dose-dependent and robust to stratification by gestational diabetes mellitus status and adjustment for socioeconomic factors.

Conclusion: Mid-childhood educational attainment is not associated with maternal glucose status. This may provide important reassurance for pregnant women and clinicians. However, maternal body mass index is associated with lower childhood educational attainment and may be modifiable with intervention before or during pregnancy.