Women over the age of 40 who give birth have a 51 percent chance of having an autistic child compared with those who bear children between the ages of 25 and 29, according to a recent news report.
The father's age also is a factor, but only if he is older and the mother is under 30, according to an article published by CNN. The piece cites findings by researchers at the University of California, Davis, which first appeared in the February issue of the journal Autism Research and examined 10 years of data from births in California. It is unknown why the mother's age is more influential than the father's on a child's chances of developing autism.
Autism Spectrum Disorders (ASD), a group of developmental disabilities that can cause significant social, communication and behavioral challenges, occur in all racial, ethnic and socioeconomic groups and are four times more likely to occur in boys than in girls, according to the Web site for the Centers for Disease Control and Prevention (CDC).
According to the CDC, more people are being diagnosed with ASD than ever before. It estimates that one in 110 children in the United States have an ASD.
"It is unclear exactly how much of this increase is due to a broader definition of ASDs and better efforts in diagnosis,'' the CDC site reports. "However, a true increase in the number of people with an ASD cannot be ruled out. We believe the increase in ASD diagnosis is likely due to a combination of these factors.''
The new findings could be a game changer for researchers trying to tackle an elusive medical matter. For years, it was believed that the genes of both parents were connected to the disorder. In the 1980s, an Israeli study linked paternal genes to the increased risk of autism.
Still it has long been known that giving birth at an older age poses health risks to babies, including higher risks of birth defects, low birth weight and certain chromosome problems such as Down syndrome.