Recent research continues to reinforce the safety of COVID-19 vaccines, even for those administered during pregnancy. A new study, presented at the 2026 Society for Maternal-Fetal Medicine Pregnancy Meeting, has found no increased risk of autism in children born to mothers who received an mRNA COVID-19 vaccine shortly before or during pregnancy, compared to children whose mothers were not vaccinated.
The findings, which researchers hope will help address lingering concerns and misinformation, add to a growing body of evidence demonstrating the safety and efficacy of COVID-19 vaccination during pregnancy. Multiple studies have previously indicated the vaccines are safe, but this research specifically focuses on the potential link to autism spectrum disorder (ASD), a concern that has been repeatedly raised despite a lack of scientific support.
Study Design and Methodology
The study involved 434 children, tracked from to , across 14 medical facilities. Half of the children were born to mothers who had received at least one dose of an mRNA COVID-19 vaccine either during pregnancy or within 30 days prior to becoming pregnant. The other half served as a control group, born to mothers who remained unvaccinated throughout the period.
Researchers evaluated the toddlers, aged between 18 and 30 months, using four standardized screening tools designed to identify potential developmental concerns. These included the Ages and Stages Questionnaire Version 3 (ASQ-3), the Child Behavior Checklist, the Modified Checklist for Autism in Toddlers, and the Early Childhood Behavior Questionnaire. It’s important to note that these screenings are not diagnostic tools; rather, they are designed to flag children who may benefit from further evaluation by a specialist.
No Significant Differences Observed
After analyzing the results from all four screening assessments, the researchers found no statistically significant differences between the two groups – those born to vaccinated mothers and those born to unvaccinated mothers. This consistency across multiple assessment methods strengthens the conclusion that COVID-19 vaccination does not appear to increase the risk of developmental concerns in children.
“The fact that there were no differences on all four of these outcomes is evidence that COVID vaccination does not result in developmental concerns for most children,” said Alycia Halladay, PhD, chief science officer at the Autism Science Foundation, who was not involved in the study. This statement underscores the importance of relying on scientific evidence to address public health concerns.
Global Consensus on Vaccine Safety and Autism
This new study aligns with the conclusions of numerous other investigations conducted over the years. A recent analysis by the World Health Organization’s (WHO) Global Advisory Committee on Vaccine Safety (GACVS), discussed on , reaffirmed that there is no causal link between vaccines and autism spectrum disorders. The GACVS, established in , provides independent scientific advice to the WHO on vaccine safety.
The WHO analysis specifically examined the relationship between vaccines containing thiomersal and ASD, as well as the broader association between vaccines in general and ASD. The review of 31 primary research studies, spanning from to , and including data from multiple countries, consistently supported the positive safety profile of vaccines used in both childhood and pregnancy.
the GACVS also assessed the potential health risks associated with vaccines containing aluminum adjuvants, reviewing studies conducted from through . A large cohort study analyzing nationwide registry data of children born in Denmark between and also found no association between the trace amounts of aluminum in some vaccines and ASD.
Reiterating Previous Findings
The WHO’s recent findings reaffirm previous conclusions reached in , , and : vaccines, including those with thiomersal and/or aluminum, do not cause autism. The organization advises all national authorities to base their vaccine policies on the latest scientific evidence.
These findings are particularly important given the ongoing spread of misinformation regarding vaccine safety. The continued reassurance from leading health organizations and rigorous scientific studies is crucial for maintaining public trust in vaccination programs and protecting both individual and community health. Vaccination remains one of the most effective tools available for preventing serious infectious diseases and improving global health outcomes.
