In a massive study of more than nine million pregnancies, a new link has been found between gestational diabetes and neurodiversity – translating to a 36% increased risk of attention-deficit/hyperactivity disorder (ADHD) and a 56% higher risk of autism spectrum disorder (ASD).
In one of the largest reviews of its kind, a new analysis of global data presented at the annual European Association for the Study of Diabetes (EASD) conference in Vienna has tied gestational diabetes to a decline in cognitive function for mothers and a higher risk of neurodevelopmental disorders in children, including ADHD and autism.
Researchers from Monash University and the National University of Singapore (NUS) pooled data from 48 observational studies involving more than nine million pregnancies across 20 countries. The review included five studies that assessed maternal cognition and 43 that examined neurocognitive outcomes in offspring up to the age of 29 years. It found that mothers who had gestational diabetes scored significantly lower on a widely used measure of cognitive function (the 30-point Montreal Cognitive Assessment), averaging 2.5 points below their peers.
For children, the disparities were even more pronounced. Those born to mothers with gestational diabetes scored nearly four points lower on IQ tests, and showed a three-point drop in measures of "verbal crystallized intelligence," which underpins language comprehension and communication. The risk of developmental delays was 45% higher, while the odds of being diagnosed with ADHD increased by 36%, and autism by 56%.
Gestational diabetes results from hormonal changes and the way the insulin converts food into energy and distributes that fuel to cells. If insulin isn't functioning as it should, or the mother is low in this hormone, sugar builds up in the blood and leads to diabetes. During pregnancy, hormones from the placenta can interfere with the way insulin works.
It's also reasonably common, developing in around 14% of pregnancies worldwide, and it usually resolves itself after birth. But it's also associated with risks during pregnancy, including preeclampsia, cesarean delivery, premature birth and neonatal hypoglycemia. Research has already established that children exposed to gestational diabetes in the womb face higher risks of obesity and diabetes later in life.
A 2023 report by the Centers for Disease Control and Prevention (CDC) reported on a huge rise in the prevalence of gestational diabetes in the US between 2016 and 2021, with scientists attributing this to several factors, including higher rates of obesity and women choosing to have children later in life. This jump is mirrored in other parts of the world, including Australia – where, in 2020-2021, almost one in five women were diagnosed with the condition during pregnancy.
However, it's worth noting that the design of this study can't establish that gestational diabetes directly causes ADHD or autism, only that there appears to be a strong association. Additionally, the review did not find evidence of changes to major brain structures or global cognitive scores across the population, suggesting that the risks may be more nuanced. As such, the authors suggest long-term studies will be critical to determine whether childhood IQ and language disparities persist into adulthood.
“Longer follow-ups across childhood are also needed to examine whether these associations persist or progress further to other worse outcomes,” said presenting author Caitlin Por from Monash University.
And while it's not clear exactly how gestational diabetes may impact brain development, researchers suggest that factors such as inflammation, cellular stress, reduced oxygen supply and high insulin levels could play a role in brain development in the womb. Nonetheless, there is a growing body of evidence linking gestational diabetes to disrupted neurocognitive functioning – and this study is the first to synthesize it as a comprehensive review.
“There are increasing concerns about the neurotoxic effects of gestational diabetes on the developing brain," said lead senior author Dr Ling-Jun Li , an assistant professor at the NUS School of Medicine. "Our findings underscore the urgency of addressing this significant public health concern that poses substantial cognitive dysfunction risks for both mothers and offspring."
While gestational diabetes is not entirely preventable, risk can be reduced by eating balanced and nutritious meals and getting regular exercise before and during pregnancy. The researchers advise that strategies to monitor and manage maternal glucose levels, along with postnatal developmental screenings, should be made a priority between clinicians and patients.
The research was presented at the Annual Meeting of The European Association for the Study of Diabetes (EASD) conference in Vienna this week (September 15-19, 2025).
Source: Monash University via Scimex
