The number of children born with autism is on the rise and so is obesity. Now researchers say the two may be linked.

In a study of more than 1,000 children, researchers found that mothers who were obese during pregnancy had a 67 percent greater chance of having a child with autism and were more than twice as likely to have a child with another developmental disorder. What’s more, moms with diabetes — which often occurs in those who are overweight — were 2.3 times more likely to have a child with developmental delay.

The findings published Monday in the journal Pediatrics are among the first to tie autism and developmental delay to the presence of metabolic conditions like obesity and diabetes in pregnant women. Researchers say their discoveries carry significant public health concerns, citing statistics showing that nearly 60 percent of American women of child-bearing age are overweight.

“It really was eye opening,” said Paula Krakowiak of the University of California at Davis who led the study. “This would add to reasons to do whatever you can to maintain your health.”

For the study, Krakowiak and her colleagues looked at over 500 children with autism, nearly 200 with other developmental delays and about 300 typically developing kids in California.

Through interviews with the children’s mothers and reviews of medical records, they found that obesity, diabetes and hypertension during pregnancy were significantly more common among mothers who gave birth to kids with developmental problems.

It’s unclear why metabolic issues like obesity would increase the odds of autism and other developmental problems, but Krakowiak said that the body’s reaction to such conditions could negatively affect a baby’s brain development.

“There are already benefits of modifying lifestyle — eating healthy and being active — but not only is it going to increase your own well-being, but it also might reduce the odds of adverse effects in your child,” Krakowiak said.