Mother's flu in pregnancy not tied to autism in children: study

Women who caught flu during pregnancy will not put their children at an increased risk of autism, a U.S. study said Monday.

Ousseny Zerbo of Kaiser Permanente Northern California and colleagues tracked 196,929 children born from 2000 through 2010 at a gestational age of at least 24 weeks.

The study, published online by the U.S. journal JAMA Pediatrics, included 1,400 mothers diagnosed with influenza and 45,231 mothers who received an influenza vaccination during pregnancy.

Of all the births, 3,101 children, or 1.6 percent, were diagnosed with autism spectrum disorders (ASD).

The results revealed no association between increased risk of ASD and influenza vaccination during the second and third three months of pregnancy.

However, the researchers did notice an increased risk of ASD with maternal vaccination in the first three months, but they explained the finding was likely "due to chance" because it was not statistically significant after adjusting for multiple comparisons.

"While we do not advocate changes in vaccine policy or practice, we believe that additional studies are warranted to further evaluate any potential associations between first-trimester maternal influenza vaccination and autism," the study concluded.