Research indicates maternal infections and fever during pregnancy might be associated with an increased risk of autism spectrum disorder (ASD), but the relationship between flu vaccination and ASD has not been explored until now.
Reporting in JAMA Pediatrics
(online, 2 January 2017), researchers studied data on 196,929 children (median age 8.3 years) of whom 3,103 had ASD. They found that, overall, neither maternal flu infection nor vaccination was associated with the risk of ASD. The analyses did show a roughly 20% increased ASD risk related to vaccination in the first trimester specifically, but the team says this finding did not have statistical significance after all adjustments (P=0), meaning it could be down to chance.
The authors conclude that the results do not indicate that policy on flu vaccination in pregnancy should change, but they say further research is needed to clarify any potential relationship between first-trimester vaccination and ASD.
 Zerbo O, Qian Y, Yoshida C et al. Association between influenza infection and vaccination during pregnancy and risk of autism spectrum disorder. JAMA Pediatrics 2016; doi: 10.1001/jamapediatrics.2016.3609