Mothers-to-be know they must be extra vigilant about what they put in their bodies—avoiding too much seafood, and making sure they get plenty of fruits and vegetables, for instance. But research has been piling up suggesting that the mother's overall weight and metabolic health before—and while—she is pregnant can also have a lasting impact on her children's physical and developmental health.

Now a new study suggests that mothers who are obese or diabetic during pregnancy are more likely to have kids with developmental disorders and possibly autism. The findings were published online April 9 in Pediatrics.

Women with type 2 or gestational diabetes were 2.3 times more likely to have a child that would have some form of developmental disorders other than autism. (Some 11.6 percent of children with developmental disorders had a mother who had had diabetes while pregnant, whereas 6.4 percent normally developing children had a mother with diabetes.) And women who were obese or had another metabolic condition were also less likely to have children with normal neuro-behavioral development, according to the study.

"Over a third of U.S. women in their childbearing years are obese, and nearly one-tenth have gestational or type 2 diabetes during pregnancy," Paula Krakowiak, a biostatician at the University of California, Davis Health System and co-author of the new study, said in a prepared statement. "Our finding that these maternal conditions may be linked with neurodevelopmental problems in children raises concerns and therefore may have serious public health implications."

For the report, Krakowiak and her colleagues studied 1,004 children aged two to five years--517 of whom had autism, 172 of whom had a different developmental disorder and 315 of whom were developing normally--and their mothers. The subjects were recruited as part of the Childhood Autism Risks from Genetics and the Environment study, which is run in California.

Autistic children whose mothers had a metabolic condition also tended to perform more poorly on language and social engagement tests than autistic children of women who did not have these conditions. And kids who had not been diagnosed with autism spectrum disorder performed worse on early learning and adaptive behavior tests if they had had a mother with one or more metabolic conditions.

The researchers are not yet sure why this link might exist. One theory is that abnormal glucose and insulin levels in a woman who is obese or has diabetes or metabolic syndrome during pregnancy might reduce the amount of oxygen and iron available to the fetal brain.

With the incidence of obesity, diabetes and autism all on the rise, Krakowiak and her colleagues noted that more study is needed into this association—and quickly.