A major new analysis is drawing fresh attention to the possible links between gestational diabetes and long-term brain health in both mothers and their children. The review, which combined data from 48 studies conducted over nearly 50 years, suggests that diabetes during pregnancy may have effects that extend well beyond childbirth, influencing memory, learning and mental health.
Author
- Adaikala Antonysunil
Senior Lecturer in Biochemistry, School of Science and Technology, Nottingham Trent University
Gestational diabetes occurs when blood sugar rises during pregnancy, usually in the second or third trimester. Unlike type 1 or type 2 diabetes, it usually disappears after the child has been born. However, women who experience it are at greater risk of developing type 2 diabetes later in life.
The condition is also becoming more common worldwide, partly because more women begin pregnancy overweight and are having children at an older age. Current estimates suggest it now affects one in seven pregnancies .
The new research , which is yet to be peer reviewed, found notable differences in outcomes for children exposed to gestational diabetes in the womb.
On average, they were 36% more likely to be diagnosed with attention deficit hyperactivity disorder (ADHD), 56% more likely to develop autism and 45% more likely to have developmental delays compared with those whose mothers had normal blood sugar during pregnancy. They also scored lower on IQ tests - nearly four points less on average - with particular difficulties in verbal skills and accumulated knowledge.
For mothers, the differences were less striking but still measurable. Those who had gestational diabetes scored about 2.5 points lower on the Montreal Cognitive Assessment, a widely used test of memory, attention and problem-solving. While this is only a modest drop, it suggests that even temporary changes in blood sugar during pregnancy could have subtle long-term effects on brain function.
Researchers also identified biological markers that may help explain these outcomes. Children born to mothers with gestational diabetes had lower levels of a protein called brain-derived neurotrophic factor, or BDNF.
This protein supports the growth and repair of brain cells and is vital for learning and memory. Reduced levels could point to slower or less resilient brain development, though the precise effect is still uncertain.
Why these links exist remains an open question. Scientists believe that high blood sugar during pregnancy may lead to inflammation and increased oxidative stress, both of which can damage cells. Changes in how the placenta works may also alter the supply of oxygen and nutrients to the developing baby. In addition, the high insulin levels often seen with gestational diabetes could influence how brain connections are formed.
Another area of focus is epigenetics - the chemical modifications that affect how genes are switched on or off. Diet during pregnancy can trigger such changes, potentially influencing how the baby's metabolism and brain develop.
Studies suggest that vitamin B12, which plays an epigenetic role in DNA repair and gene regulation, may be especially important. Low levels of B12, often linked to diets high in ultra-processed food, have been associated with poorer outcomes in foetal development , though the evidence is not yet conclusive.
It is important to stress the limits of the research. All of the studies included in the analysis were observational, meaning they can show associations but cannot prove cause and effect. Many other factors - including genetics, family environment and wider health inequalities - also shape outcomes for both mothers and children.
The fact that no major structural brain differences were detected between exposed and non-exposed children suggests that any effects are subtle, perhaps confined to language, attention or memory.
Even so, the findings carry important implications for healthcare. They underline the value of careful glucose monitoring during pregnancy and of lifestyle approaches such as healthy diet and regular physical activity, which are proven ways of managing gestational diabetes. Medical treatment, where required, also plays a crucial role in reducing risks.
For mothers, the research suggests that support should continue after birth, not only to monitor blood sugar but also to keep an eye on cognitive health. For children, early developmental checks could help identify those who might benefit from extra support in learning or behaviour.
Not about blame
Researchers emphasise that these findings are not about blame. Gestational diabetes arises from a complex mix of biological, genetic and environmental factors, many of which are outside individual control. Rather, the analysis points to the need for broader public health strategies and improved support systems during and after pregnancy.
As one of the most comprehensive reviews of its kind, the study adds weight to the idea that gestational diabetes may have lasting consequences that extend beyond pregnancy itself. With prevalence rising worldwide , better understanding of these links is vital for protecting the wellbeing of both mothers and their children.
Future studies may help refine dietary and lifestyle recommendations, exploring how nutrients such as vitamin B12 interact with gestational diabetes. By deepening our understanding of these processes, researchers hope to develop more targeted ways to safeguard brain health across generations.
The findings suggest that gestational diabetes is not only a temporary disruption of blood sugar but may also be linked to subtle, lasting changes in cognitive outcomes. As awareness grows, so too does the importance of early care and sustained support for families affected by this increasingly common condition.
Adaikala Antonysunil receives funding from Diabetes Research Wellness Foundation, BBSRC, Rosetrees Trust and Society of Endocrinology.
