Women who don't take steps to treat a fever during pregnancy may be increasing their risk of having a child with autism or another developmental disorder, a new study suggests.
The children of women who had fevers while pregnant were at twice the risk of other children to develop a developmental problem, the researchers found. However, among women who treated their fevers, the risk of having a child with autism or another developmental disorder was the same as among those who didn't have fevers.
Fevers cause inflammation, and the new finding adds to the evidence that inflammation may affect the development of autism, said study researcher Irva Hertz-Picciotto, a professor of public health at the University of California, Davis.
While the research suggested an association, more work is needed to understand the ways fever and other forms of inflammation during pregnancy may affect a child's development, the researchers said.
The study was one of the first to look at a possible link between pregnant women’s fevers and a child’s risk of having autism or another developmental disorder, the researchers said. Previous studies have suggested a link between women with obesity or diabetes and the chance of having a child with autism. Fevers cause short-term inflammation, and obesity and diabetes result in long-term inflammation, the researchers said. Together, the findings suggest that inflammation is at work in the development of autism.
When the body fights a fever-causing virus or bacterium, the immune system’swhite blood cells release chemicals called cytokines, and these cause inflammation. Cytokines also could cross into the placenta and affect a fetus's neural development, Hertz-Picciotto said.
"We recommend that pregnant women who develop fever take anti-pyretic medications and seek medical attention if their fever persists," said study researcher Ousseny Zerbo, who was a doctoral student at UC Davis while the study was conducted.
Of the 1,122 children in the study, more than half (538) had autism. Another 163 children had other developmental disorders, and 421 were normally developing children. The participants are involved in larger study aimed at understanding the causes of autism.
The women completed questionnaires about their health during pregnancy when their children were between the ages of 2 and 5.
About one in six U.S. children has a developmental disorder, ranging from mild speech impairments to serious disabilities. The rate of autism is about one in 88, according to the most recent statistics available from the Centers for Disease Control and Prevention. While autism can be detected as early as age 2, it also can go undiagnosed for years, the CDC says.
The researchers also found that among women who had the flu during pregnancy, there was no increased risk of having a child with a developmental disorder.
The study was published yesterday (May 23) in the Journal of Autism and Developmental Disorders.?
Pass it on: Having a fever during pregnancy could double the chances of having an autistic baby, but treating the fever eliminates the risk.
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