New research has found mothers with diabetes - of any type - are more likely to have kids with autism.
Researchers at California healthcare company Kaiser Permanente looked at health data from 400,000 children born between 1995 and 2012, and found a much stronger link than previously known.
"The risk of autism spectrum disorder was increased in children of mothers with the three main types of diabetes that complicate pregnancy, findings that add new information on type 1 diabetes and extend what is already known about type 2 and gestational diabetes," the authors said in a statement.
Women who develop gestational diabetes before their third trimester are most at risk.
It doesn't conclusively prove diabetes causes autism however. The origins of the condition, more common in boys than girls, remain murky.
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But diabetes expert Jim Mann of the University of Otago says the suspicion diabetes could play a role has been floating for 20 years or so now.
"The difference between this study and the previous study is the previous studies have suggested a link between autism and type 2 diabetes, and this study suggests a link between autism and type 1 diabetes," he told Newshub.
Women who develop gestational diabetes before their third trimester are most at risk.
Prof Mann says diabetes has many more health effects than people realise.
"Diabetes now is one of the major causes of heart disease and all other diseases - like strokes, some cancers, blindness, kidney failure. It's just a litany of bad news stories with diabetes."
While study sheds new light on autism's causes, it doesn't point to a cure or treatment.
"The frustrating thing I guess that we don't really know what we can do about it," said Prof Mann.
The research was published in the Journal of the American Medical Association.
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Newshub.
