New research presented at the Society for Maternal-Fetal Medicine (SMFM) 2026 Pregnancy Meeting™ offers reassuring evidence for expectant mothers and their future children: the mRNA COVID-19 vaccine is not associated with an increased risk of autism or other neurodevelopmental problems in children born to vaccinated mothers. The findings, released on , address ongoing concerns about the potential impact of COVID-19 vaccination during pregnancy on infant neurodevelopment.
Both mRNA vaccines and protein subunit vaccines are recommended during all stages of pregnancy to protect maternal and infant health. This study specifically focuses on the mRNA vaccine, one of the two types currently available in the U.S.
The research involved a prospective observational study of 434 children, aged between and , conducted by researchers from the Maternal-Fetal Medicine Units Network between and . Half of the children (217) were born to mothers who had received at least one dose of the mRNA vaccine during or within 30 days prior to pregnancy. The other half served as a control group, born to mothers who had not received the mRNA vaccine during the same timeframe.
“Neurodevelopment outcomes in children born to mothers who received the COVID-19 vaccine during or shortly before pregnancy did not differ from those born to mothers who did not receive the vaccine,” explained Dr. George R. Saade, Professor and Chair of Obstetrics and Gynecology, and Associate Dean for Women’s Health, at Macon & Joan Brock Virginia Health Sciences at Old Dominion University in Norfolk, VA.
To ensure a robust comparison, researchers carefully matched vaccinated and unvaccinated mothers based on several key factors, including the type of delivery site (hospital, birth center, etc.), delivery date, insurance status, and race. The study excluded participants who delivered preterm (before 37 weeks of gestation), those with multifetal pregnancies, and those whose children were born with major congenital malformations, further refining the study population.
The children were assessed for neurodevelopmental signs using a battery of standardized screening tools, including the Ages and Stages Questionnaire Version 3, the Child Behavior Checklist, the Modified Checklist for Autism in Toddlers, and the Early Childhood Behavior Questionnaire. These assessments evaluated key developmental areas such as communication, gross and fine motor skills, problem-solving abilities, and personal-social interaction. Researchers then compared the assessment scores between the two groups.
The findings consistently showed no significant differences in neurodevelopmental outcomes between the children born to vaccinated and unvaccinated mothers. This suggests that maternal COVID-19 vaccination during or shortly before pregnancy does not increase the risk of neurodevelopmental issues in their offspring.
“This study, conducted through a rigorous scientific process in an NIH clinical trials network, demonstrates reassuring findings regarding the long-term health of children whose mothers received COVID-19 vaccination during pregnancy.”
Brenna L. Hughes, MD, MSc, Edwin Crowell Hamblen Distinguished Professor of Reproductive Biology and Family Planning and Interim Chair of the Department of Obstetrics and Gynecology at Duke University in Raleigh, NC.
This research builds upon previous studies investigating the safety of COVID-19 vaccination during pregnancy. A study published in in JAMA Pediatrics, for example, indicated that in utero vaccination was not associated with neurodevelopmental concerns up to 18 months of age. That study, the Assessing the Safety of Pregnancy During the Coronavirus Pandemic (ASPIRE) study, enrolled pregnant individuals starting in .
The current study, and others like it, are crucial in addressing public health concerns and providing evidence-based information to pregnant individuals and healthcare providers. Early in the pandemic, pregnant individuals were excluded from initial large-scale clinical trials of COVID-19 vaccines, leading to understandable questions about potential fetal exposure risks. Researchers have since prioritized investigating these concerns.
It’s important to remember that neurodevelopmental disorders are complex and can be influenced by a variety of genetic and environmental factors. Fetal exposure to maternal inflammation from infections like influenza and rubella has previously been linked to increased risks of neurodevelopmental and psychiatric impairments. This research helps to clarify the role, or lack thereof, of COVID-19 vaccination in this context.
The study was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The researchers emphasize that the content and conclusions are solely their responsibility and do not necessarily reflect the official views of the National Institutes of Health.
