By Stephanie Stahl

PHILADELPHIA (CBS) – New research identifies the risk factors that increase the chances of women having children with developmental disorders.

Diabetes and obesity are at epidemic levels in women of the child-bearing age.  Now, a new study is linking the two conditions to an increased risk for autism.

“We found that mothers who were obese and diabetic during pregnancy had a risk four times greater, than mothers who didn’t, of the child developing autism,” said Dr. Dani Fallin, of the John’s Hopkins Bloomberg School of Public Health.

The study, published in the Pediatrics Journal, also found a higher autism risk in mothers who developed gestational diabetes.

“There are many hypotheses about how a disrupted immune system during brain development can create developmental disabilities,” Dr. Fallin said.

Dr. Paul Wang from Autism Speaks says the study helps the understanding of what causes autism, which is also partially genetic.

“I think it’s very clear actually,” Dr. Wang says. “The processes that underlie autism, in a large majority of cases, start before birth. That is true for genetic factors, true for things like pollution exposure.”

Experts say it’s important for pregnant women to avoid a variety of potential autism risks such as gaining too much weight.

Stephanie Stahl