Mothers who reported having the flu during pregnancy were at least twice as likely to have a child with autism as those who did not report having the flu, according to new survey results from a Danish study. While the study does not suggest that high fever — or flu — causes autism, many experts said the correlation reinforces recommendations that all pregnant women should get the flu shot.
The study by researchers in Denmark and the U.S. Centers for Disease Control and Prevention looked at nearly 97,000 children ages 8 to 14 who were born in Denmark between 1997 and 2003, only 1 percent of whom were diagnosed with an autism spectrum disorder. The researchers interviewed the mothers during their pregnancy and after delivery about any infections and high fevers they’d experienced while pregnant, as well as whether they had used antibiotics.
Although the study was not designed to ask about cases of the flu, mothers who reported having the flu during their pregnancy were two times more likely to have a child with autism, according to the study published Monday in the journal Pediatrics. Those whose fever persisted for a week or more before their third trimester were three times more likely to have a child on the autism spectrum, the study found.