What Causes Autism? Flu Shot During Pregnancy Not Linked To Diagnosis In Children, New Study Finds

Receiving a flu shot while pregnant will not put a child at risk of later being diagnosed with autism. A new study published Tuesday in JAMA Pediatrics concluded that there is no link that finds the children of women who catch the flu while pregnant or receive a flu shot during pregnancy are later diagnosed with autism.

The study pulled medical records from 196,929 children all born at the same Northern California hospital, Kaiser Permanente facilities, between 2000 and 2010. Of those, 3,101 were diagnosed with autism spectrum disorder, NPR reported. Although there was no direct link found in mothers who had the flu while pregnant and their child being diagnosed with autism, there was a slight increased risk for mothers who received a flu vaccine during their first trimester.

However, researchers noted that due to the small number of children, the autism diagnosis could have been by chance. "We feel it should be reassuring for prospective mothers," said Lisa Croen, senior author of the study who also works at the hospital. "The way we feel people should interpret this is that there is really not any increased risk for autism, and we're recommending no changes in the vaccine policy."

Despite their findings, Croen and fellow researchers suggest that additional research needs to be done due to the results of previous studies that have found that the mother’s immune system may be linked to an increased risk of autism.

The Centers for Disease Control and Prevention recommends that women should get the flu vaccine during each pregnancy. The vaccine can help protect the woman and their growing baby. Women who catch the flu during pregnancy are at risk of premature labor and delivery. It is suggested that women who will be pregnant during the flu seasons are encouraged to get vaccinated by the end of October.