Objective: We aimed to evaluate cognitive function in adult offspring of women with diet-treated gestational diabetes and to study potential associations with maternal glucose values.
Materials and methods: In 2003-2005 cognitive function was assessed in a cohort of 18-27 year old offspring of women with diet-treated gestational diabetes mellitus (n = 153) and offspring from the background population (n = 118). The main outcome measure was global cognitive score derived from Raven's Progressive Matrices and three verbal subtests from the Weschler Adult Intelligence Scale. Maternal fasting- and 2-hour blood glucose values from the diagnostic oral glucose tolerance test were used as exposure variables.
Results: Offspring of women with gestational diabetes mellitus had a lower global cognitive score, than offspring from the background population (93.1 vs. 100.0, P<0.001). However, when adjusted for maternal age at delivery, parity, smoking during pregnancy, pre-pregnancy overweight, family social class, parental educational level, gender, birth weight, gestational age, perinatal complications and offspring age at follow-up, the difference was no longer statistically significant. Offspring global cognitive score decreased significantly with increasing maternal fasting glucose (β = -4.5, 95% CI -8.0 to -0.9, P = 0.01) and 2-hour glucose (β = -1.5, -2.9 to -0.2, P = 0.03) in univariate general linear models, but not when adjusted for family social class and parental educational level.
Conclusions: Lower cognitive test scores in adult offspring of women with diet-treated gestational diabetes were explained by well known predictors of cognitive function, but not by maternal hyperglycaemia during pregnancy. We find it reassuring that mild intrauterine hyperglycaemia does not seem to have adverse effect on offspring cognitive function.