A condition suffered by more than 330,000 pregnant women has been linked to a higher risk of autism.

Gestational diabetes, impacting around nine percent of pregnant women in the United States, is experiencing a rise. This is attributed to factors similar to those driving the wider diabetes epidemic, such as an increase in maternal age and growing obesity rates.

With more women starting pregnancy with these risk elements, their bodies find it difficult to handle the additional insulin required during pregnancy, leading to lasting health effects for both the mother and child.

A research team from Australia and Singapore discovered that women with elevated blood sugar levels during pregnancy scored lower on a cognitive test frequently used for dementia screening.

Their offspring also tended to have lower scores on IQ tests and were at a greater risk of developmental issues, including partial delays and attention-deficit/hyperactivity disorder (ADHD).

The team found that these children had a 56 percent increased risk for ASD compared to children whose mothers did not have gestational diabetes. 

Researchers propose that gestational diabetes interferes with crucial brain development processes through inflammation, stress, and nutrient imbalances, resulting in changes in cognitive abilities and an increased risk for neurodevelopmental disorders such as ADHD and autism spectrum disorder (ASD).

Dr. Ling-Jun Li, the lead author and assistant professor at the School of Medicine, National University of Singapore, stated, ‘There are growing concerns about the neurotoxic effects of gestational diabetes on the developing brain.’

‘Our findings underscore the urgency of addressing this significant public health concern that poses substantial cognitive dysfunction risks for both mothers and offspring.’

Gestational diabetes affects more than 330,000 American women. It usually goes away immediately after pregnancy, but it leaves a lasting mark on both the mother’s and child’s future health

The study comes as Health Secretary Robert F Kennedy Jr is on a crusade to uncover environmental causes of autism.

However, the latest study has suggested it could be social factors rather than a single toxin.

Researchers behind the new study conducted a systematic review of observational studies through April 2024 to assess the significant cognitive deficits of gestational diabetes.

The analysis, encompassing data from more than nine million pregnancies globally, revealed that the condition is associated with significant cognitive deficits in children.

The meta-analysis found that children born to mothers with gestational diabetes exhibited statistically significant decreases in cognitive scores.

Specifically, their overall IQ scores were an average of about four points lower than those of children not exposed to the condition. 

Furthermore, these children showed a notable reduction in verbal crystallized intelligence, including smaller vocabularies and weaker verbal reasoning, with scores averaging more than three points lower.

Additionally, the study identified significantly higher risks for several neurodevelopmental disorders in children whose mothers had gestational diabetes.

The CDC chart shows the percentages of mothers with gestational Diabetes by maternal age in 2016 and 2021. This rise is fueled by the same factors driving the wider diabetes crisis, which include more women having children later in life and increasing obesity rates 

These children faced a 45 percent higher risk for both total and partial developmental delays. They were also 36 percent more likely to be diagnosed with ADHD.

While the exact link remains unclear, scientists suggested that gestational diabetes may influence a child’s brain development through several key mechanisms.

Factors such as heightened inflammation, cellular stress, reduced oxygen supply, and elevated insulin levels in the womb can potentially alter how the fetal brain develops. 

These changes are thought to lay the groundwork for the differences in learning and cognitive abilities seen later in childhood.

The study is being presented at this year’s Annual Meeting of The European Association for the Study of Diabetes (EASD) in Vienna, Austria.

Gestational diabetes mellitus (GDM) usually occurs in the second and third trimesters of pregnancy. 

The exact cause of GDM is unclear, but researchers have found that hormones produced by the placenta, which support the baby’s growth, can sometimes block the mother’s insulin. 

This causes the body to become less responsive to insulin, a state known as insulin resistance. 

The mother’s body is then unable to use insulin effectively, requiring it to produce more. If it cannot produce enough insulin during pregnancy, glucose remains in the blood, leading to high blood sugar.

While GDM is treatable and generally goes away after pregnancy, it can pose health risks to both the mother and her baby if left unmanaged. Pregnant women with the condition should follow a healthy eating plan and be physically active. 

Because it is such a stealthy condition with no obvious symptoms, doctors proactively screen for it. The standard method is a two-part ‘glucose challenge’.

Around weeks 24 to 28 of pregnancy, every expectant mother is asked to drink a sweet sugar solution. 

An hour later, her blood is drawn. If her sugar levels are too high, it doesn’t mean she has GDM, but it flags her for the definitive follow-up test.

This second test is the real decider. After fasting overnight, the expectant mother drinks an even sweeter solution and has her blood tested multiple times over a few hours. 

If her body struggles to process that sugar surge on two or more of those tests, she receives a diagnosis.

The process allows doctors to identify the condition and start management long before it can cause complications, turning a silent risk into a manageable part of prenatal care.

A woman is more likely to develop gestational diabetes if she has certain risk factors, such as having had it in a previous pregnancy, previously delivering a large baby over nine pounds, being overweight or having a family history of type 2 diabetes.

Other factors that increase risk include having polycystic ovary syndrome (PCOS) or being of African American, Hispanic, Native American, Alaska Native, Native Hawaiian or Pacific Islander descent.