The mRNA COVID-19 vaccine is not associated with autism or other neurodevelopmental problems in children whose mothers received the vaccine immediately before or during pregnancy, according to new research presented today at the Society for Maternal-Fetal Medicine (SMFM) 2026 Pregnancy Meeting™.
There are two types of COVID-19 vaccines recommended for use in the U.S.: the messenger ribonucleic acid (mRNA) vaccine and a protein subunit vaccine. Both types of COVID-19 vaccine are recommended and safe to receive during any stage of pregnancy to protect both maternal and infant health.
Researchers from the Maternal-Fetal Medicine Units Network studied 434 children between the ages of 18 months and 30 months for signs of autism or other neurodevelopmental problems. In this multi-center prospective observational study conducted between May 2024 and March 2025, 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 were born to mothers who had not received mRNA vaccination during or within 30 days prior to pregnancy.
"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," said senior researcher George R. Saade, MD, 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.
Mothers who received the mRNA COVID-19 vaccine were matched with mothers who did not receive the vaccine based on the delivery site where they gave birth (hospital, birth center, etc.), delivery date, insurance status, and race. Participants were excluded from both study groups if they delivered preterm under 37 weeks, if they had a multifetal pregnancy, or had a child born with a major congenital malformation.
Children born to both groups were tested for neurodevelopmental problems at age 1 ½ - 2 ½ years, using the Ages and Stages Questionnaire Version 3 that assesses and tracks child development in five main areas: communication, gross motor skills, fine motor skills, problem-solving, and personal-social interaction. Additionally, the researchers compared the children's assessment scores from the Child Behavior Checklist, Modified Checklist for Autism in Toddlers, and the Early Childhood Behavior Questionnaire.
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 study was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.