Gestational diabetes linked to higher risks of autism, ADHD and lower IQ in children, large review finds

A large systematic review and meta-analysis has found that gestational diabetes is associated with lower cognitive scores in children and substantially higher risks of developmental delays, attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD).

Researchers who pooled data from observational studies covering more than 9 million pregnancies worldwide reported that children born to mothers with gestational diabetes scored on average about four points lower on overall IQ tests and more than three points lower on measures of verbal crystallized intelligence, which captures vocabulary and verbal reasoning. The analysis also found a 45 percent higher risk of total and partial developmental delays, a 36 percent higher risk of ADHD and a 56 percent higher risk of ASD among exposed children compared with those whose mothers did not have the condition.

The review, conducted by investigators in Australia and Singapore and presented at the European Association for the Study of Diabetes annual meeting in Vienna, examined observational studies through April 2024 and used pooled data to quantify neurocognitive outcomes associated with gestational diabetes. Lead author Dr. Ling‑Jun Li, an assistant professor at the National University of Singapore’s medical school, said the findings “underscore the urgency of addressing this significant public health concern that poses substantial cognitive dysfunction risks for both mothers and offspring.”

Gestational diabetes mellitus (GDM) typically develops in the second or third trimester when pregnancy hormones can interfere with the mother’s insulin response, producing insulin resistance and elevated blood glucose levels. The condition usually resolves after delivery but has been linked in prior studies to higher long-term risks of type 2 diabetes in mothers and metabolic effects in their children.

In the United States, gestational diabetes affects roughly 9 percent of pregnancies — a proportion that translates to hundreds of thousands of affected pregnancies each year. Public health experts say the rise in gestational diabetes is being driven largely by the same forces behind the broader diabetes epidemic, including older maternal age and rising rates of overweight and obesity.

Investigators reported several biological mechanisms that might explain the associations with neurodevelopment. High maternal blood sugar can alter the intrauterine environment through increased inflammation, cellular stress, reduced oxygen availability and elevated insulin and nutrient levels in the womb. Those changes have the potential to affect fetal brain formation and subsequent cognitive function, the researchers said, although they noted that observational studies cannot prove causation.

The study authors also described standard clinical approaches to identifying and managing gestational diabetes. Because the condition often has no obvious symptoms, clinicians commonly screen all pregnant women between about 24 and 28 weeks with a two-step glucose challenge: an initial one-hour screening after drinking a sweet solution followed, if needed, by a fasting multi-hour diagnostic glucose tolerance test. When diagnosed, gestational diabetes is typically managed with dietary guidance, physical activity and, when necessary, medication or insulin to control blood glucose levels.

Medical guidelines identify several risk factors that increase the likelihood of GDM, including prior gestational diabetes, a history of delivering a very large baby, overweight or obesity, a family history of type 2 diabetes, polycystic ovary syndrome, and certain racial and ethnic backgrounds. Clinicians emphasize early prenatal care, routine screening and glucose management to reduce pregnancy complications.

The review’s authors said their findings add to a growing body of evidence linking maternal metabolic conditions during pregnancy to offspring neurodevelopment. They called for continued research to clarify mechanisms, to evaluate whether tighter glucose control during pregnancy can reduce neurodevelopmental risks, and to identify interventions that could mitigate long-term effects for mothers and children.

Because the pooled analysis relied on observational data from multiple study designs and settings, the researchers and independent experts caution that associations do not establish a direct causal pathway and that unmeasured factors could influence results. Still, the scale of the associations reported — including increased risks for ASD and ADHD — highlights the importance of screening, diagnosis and management of gestational diabetes as part of prenatal care.

Clinicians and public health officials say the findings reinforce existing recommendations for routine GDM screening in pregnancy and for postpartum follow-up, including monitoring mothers for persistent hyperglycemia and advising healthy lifestyle measures that may benefit both maternal and child health.