Flu and Fever in Pregnancy Is Linked to Autism Risk

A new study shows that children whose mothers had the flu or ran a fever lasting more than a week during pregnancy had an increased risk of developing an autism spectrum disorder. The study analyzed data collected from 97,000 mothers of children born from 1997 through 2003 and found that while there was no association between mothers who reported common respiratory or sinus infections, common colds, urinary tract or genital infections during pregnancy and autism in their children, those whose mothers reported influenza during pregnancy had twice the risk of being diagnosed with autism before age 3, and those whose mothers had a fever for more than seven days had a three-fold risk. There also was a small increased risk of autism after the mother’s use of various antibiotics during pregnancy, although the study did not specify the conditions for which the antibiotics were prescribed.

U.S. health officials caution that the new study is exploratory and does not offer a specific cause of the developmental disability. “The study is really exploratory, and more research needs to be done to understand how maternal infections, as well as other risk factors, influence the risk of autism spectrum disorders,” says Coleen Boyle, director of the Centers for Disease Control and Prevention’s (CDC) National Center on Birth Defects and Developmental Disabilities. “We need to have more  information to get a better sense of what’s going on here.” Therefore, says Marshalyn Yeargin-Allsopp, chief of the CDC’s Developmental Disabilities branch, for now, the standard clinical recommendations for treating pregnant women suffering from fever or flu should not change as a result of this new preliminary finding.

The study was published in the November 12 issue of Pediatrics.