Prenatal tetanus, diphtheria and acellular pertussis, or Tdap, vaccination does not increase risk of autism spectrum disorder in children, according to a study published in Pediatrics.
Oakland, Calif.-based Kaiser Permanente researchers examined the autism diagnosis for 81,993 children born between Jan. 1, 2011 and Dec. 31, 2014. The vaccination coverage ranged from 26 percent for the 2012 birth cohort to 79 percent for the 2014 cohort.
The study shows the autism spectrum disorder incidence rate in children was 1.5 percent in the group with Tdap-vaccinated mothers and 1.8 percent in the unvaccinated mothers' group. The autism rates in the U.S. average 1.7 percent.
"With waning immunity against pertussis in the United States, it has become very important for pregnant women to be immunized against pertussis," said Tracy A. Becerra-Culqui, PhD, a post-doctoral research fellow with Kaiser Permanente Southern California's research and evaluation department and lead author of the study. "It is an immunity they pass on to their unborn baby. Pregnant women can be reassured by this study that there is no indication of an increased risk of autism spectrum disorder in children after being exposed prenatally to the Tdap vaccine."