Mother's Birthplace May Affect Autism Risk in Kids
Some foreign-born mothers now in U.S. are more likely to have children with the disorder, study finds
Additionally, for a specific type of the disorder that included severe emotional outbursts and impaired expressive language, U.S.-born Hispanic and black mothers, and foreign-born black and Central/South American mothers were more likely to have a child with this type of autism than U.S.-born white mothers.
The study wasn't designed to tease out the reasons behind this association, but Ritz has some theories. She believes that it's possible that "a child is more likely to develop an ASD if the mother emigrated from a country which had political unrest or wars in the recent past."
Even if those events were 20 or 30 years ago, it could still have an effect, she said. The mother giving birth may have witnessed atrocities of war or other trauma as a child, perhaps programming her to react to stress in a certain way. These mothers may react to stress in a certain way when pregnant, and that could affect the baby's ''brain wiring," she speculated.
As for whether these mothers can obtain ideal care and a prompt diagnosis for an autism spectrum disorder, Ritz cannot say, as it was outside the scope of the study. However, the average age at diagnosis for all the youngsters in this study was in the child's third year, according to the study.
"It's an interesting study to have done. It's a first step to begin to try in a more detailed fashion to identify other causes of autism," said Dr. Trevor Resnick, chief of neurology at Miami Children's Hospital. Resnick was not involved in the research, but reviewed the study's findings.
Pinning down the cause of autism spectrum disorders is complex, he said. Experts know genetic, metabolic and structural factors affect risk. "We know there is not one cause, there are multiple causes," he said.
There may even be multiple causes within one child, Resnick noted.
What the new study seems to identify is the risk of autism in different ethnic groups, he said. But the common factor is the immigrant status, not the ethnicity itself, he noted.