No Link Between Flu or Flu Vaccine and Autism, Study Finds

While previous studies looking at possible links between influenza (flu) during pregnancy and autism spectrum disorder (ASD) have produced mixed results, a new study shows that babies of pregnant women who get the flu or who are vaccinated against the flu do not have an increased risk for ASD. In the study, researchers analyzed data on 196,929 children born between 2000 and 2010 in the Kaiser Permanente Northern California healthcare system after at least 24 weeks’ gestation. During follow-up periods ranging from two to 15 years, only 1.6 percent of children were diagnosed with ASD. And, of those mothers, fewer than 1 percent had the flu while pregnant, and 23 percent had gotten a flu vaccine.

A second study published in the same issue of JAMA Pediatrics also found no link between vaccines against influenza A (H1N1) during pregnancy in 2009-2010 and complications later in life for more than 60,000 Danish children. “There have been a lot of fears about vaccines, but the data suggest they are effective and don’t increase the risk of autism and other perinatal complications,” said Loralei Thornburg, MD, a high-risk pregnancy expert at the University of Rochester Medical Center in New York.