Watch CBS News

Health Watch: Risk of Autism in Siblings Significantly Higher Than Previously Thought

PHILADELPHIA (CBS) - A surprising discovery about autism - it runs in families, among siblings, at rates higher than previously thought. Health Reporter Stephanie Stahl is On Your Side with more.

Autistic siblings are much more common than many realize, according to ground breaking new research. It says couples who have one child with autism have an increased risk of having more with the complex neurological disorder.

Crystal Gallegos' 4-year-old son, William, has autism, so she knew what to look out for when her daughter Sophia came along.

"We noticed she was delayed at six months old. She could not sit up on her own. At a year, again no speech, no language. She wasn't imitating sounds," said Crystal.

A new study in the journal "Pediatrics" shows the Gallegos family is not alone. Researchers looked at 664 babies who had an autistic sibling. They found those babies had a 20 times greater chance of having autism as well. In families with two autistic children, the risk of another sibling with the disorder increases to 32 percent.

(Gallery: Celebrity Autism Advocates)

"Our findings indicate that the incidence of autism or the recurrence of autism in families is at least double what we thought it was previously," said Dr. Ted Hutman, Study Researcher.

About one in 110 children in the United States has autism. Experts say early diagnosis is important because behavioral treatment works best if started at a young age. With the sibling risk even higher now experts say doctors will use the new findings to counsel parents of autistic children who want to have more kids.

"It's useful information from the aspect of family planning," said Dr. Hutman.

It's already known that autism is more common in boys than girls. In this study, boys with autistic siblings had a 26 percent risk of autism compared to 9 percent of girls.

For more information on autism, click here.

For more information on Autism Speaks, click here.

Reported by Stehphanie Stahl, CBS 3

View CBS News In
CBS News App Open
Chrome Safari Continue
Be the first to know
Get browser notifications for breaking news, live events, and exclusive reporting.