Gestational diabetes mellitus (GDM) is a condition of glucose intolerance that first manifests or is first recognized during pregnancy. Although it often resolves after delivery, evidence indicates that it may carry longer-term consequences for both the mother and her child. Some epidemiological studies suggest that GDM is linked with cognitive impairments in mothers during pregnancy and elevated risks of neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in children.
On September 15 to 19, at the Annual Meeting of The European Association for the Study of Diabetes (EASD), a large systematic review pooling data from 48 observational studies, encompassing over 9 million pregnancies from 20 countries, presented the associations between gestational diabetes and cognitive outcomes in mothers and their offspring.
Among five studies assessing maternal prenatal cognitive function, mothers with a history of GDM scored on average 2.47 points lower on the Montreal Cognitive Assessment (MoCA; out of 30) compared to non-GDM controls. In 43 studies of children (age range from birth to 29 years), offspring of mothers with GDM had average IQ reductions of 3.92 points and a 3.18 point reduction in verbal crystallized intelligence (language comprehension and verbal reasoning). Relative to unexposed children, exposed children had a 45% higher risk of developmental delays (total or partial), a 36% greater likelihood of ADHD, and a 56% increased risk of ASD. No consistent significant differences were detected in total brain structural metrics or in broad general cognitive scores across studies.
“Longer follow-ups across childhood are also needed to examine whether these associations persist or progress further to other worse outcomes,” noted Caitlin Por, a Medical Student at Monash University, Melbourne, Australia.
Additional research supports a link between maternal diabetes (pre-existing or gestational) and increased risk of neurodevelopmental conditions in children. For example, research by Kaiser Permanente’s Department of Research & Evaluation has examined maternal hemoglobin A1c (HbA1c) levels in early pregnancy and later ASD risk in offspring.
Children whose mothers had early-pregnancy HbA1c levels greater than 6.5% were nearly twice as likely to be diagnosed with autism within the first four years of life compared to children of mothers with HbA1c below the normal range. More severe forms of maternal diabetes (such as type 1) are associated with a higher offspring risk of neurodevelopmental outcomes than milder or gestational forms, suggesting a dose-response or gradient effect. The studies emphasize that maintaining good glycaemic control during pregnancy, and ideally before conception, may be an important preventive measure.
While definitive data is still limited, several plausible biological pathways have been proposed to explain how gestational diabetes might influence maternal cognition and fetal brain development: Elevated maternal glucose may trigger inflammatory cascades and oxidative stress in maternal and placental tissues, which can affect development or synaptic pruning in the fetus. Additionally, dysregulated insulin and insulin signaling can influence neurotrophic pathways and energy metabolism in the developing brain, potentially disrupting neural growth or connectivity.
Given the rising global prevalence of gestational diabetes, the observed associations with maternal and offspring cognitive outcomes carry significant public health concern. Early screening for and tight management of blood glucose levels in pregnant women or those planning pregnancy are more important than ever. Also, public-health strategies to reduce obesity, metabolic syndrome, and diabetes in women of childbearing age may have benefits down the line for neurodevelopment in the next generation.
