Administering an mRNA COVID-19 vaccine either shortly before conception or at any stage throughout pregnancy shows no association with autism spectrum disorder or other developmental issues in offspring, as revealed by a significant study showcased at the Society for Maternal-Fetal Medicine’s 2026 Pregnancy Meeting. These results offer fresh insights into the enduring health outcomes for children whose mothers received vaccination in proximity to their pregnancy period.
In the U.S., healthcare authorities endorse two primary COVID-19 vaccine formulations: the messenger RNA (mRNA) type and the protein subunit variant. Experts deem both options safe for use across every trimester of pregnancy, advocating their application to protect the well-being of both expectant mothers and their babies.
Examination of 434 Young Children
Scientists from the Maternal-Fetal Medicine Units Network spearheaded this research effort. They meticulously examined 434 toddlers, aged between 18 and 30 months, screening them for indicators of autism spectrum conditions and additional developmental milestones.
Designed as a forward-looking, multi-site observational study, the project unfolded from May 2024 through March 2025. Exactly half of the participants—217 children—had mothers who obtained at least one dose of the mRNA COVID-19 vaccine either while pregnant or within the 30 days preceding pregnancy. The other half, also 217 children, came from mothers who had not received any mRNA COVID-19 vaccine during pregnancy or in the 30 days leading up to it.
“Children born to mothers vaccinated with the COVID-19 mRNA vaccine during pregnancy or just prior exhibited neurodevelopmental results indistinguishable from those of children whose mothers forewent the vaccine,” explained lead investigator George R. Saade, MD, who holds positions as Professor and Chair of Obstetrics and Gynecology, as well as Associate Dean for Women’s Health, at Macon & Joan Brock Virginia Health Sciences at Old Dominion University in Norfolk, Virginia.
Methodology for Evaluating Developmental Progress
To ensure the highest level of precision in their comparisons, the research team matched mothers who received the vaccine with those who did not, considering factors such as the delivery location (whether hospital, birthing center, or other facility), the exact delivery date, insurance coverage details, and racial or ethnic background. They deliberately excluded certain cases from both cohorts, such as pregnancies concluding before 37 weeks gestation, those involving multiples like twins or triplets, or instances where the child presented with a significant birth defect.
Once the children attained the age range of 1.5 to 2.5 years, the investigators employed the Ages and Stages Questionnaire, Third Edition (ASQ-3), a validated instrument that gauges advancement across five critical domains: communication abilities, gross motor functions, fine motor capabilities, problem-solving skills, and personal-social interactions. In addition, the researchers scrutinized data from the Child Behavior Checklist, the Modified Checklist for Autism in Toddlers (M-CHAT), and the Early Childhood Behavior Questionnaire to gain a more comprehensive picture of behavioral traits and developmental trajectories.
“Through this meticulously executed study within an NIH-supported clinical trials framework, we uncover encouraging evidence about the sustained health prospects for offspring of mothers who got the COVID-19 vaccine while pregnant,” stated Brenna L. Hughes, MD, MSc, the Edwin Crowell Hamblen Distinguished Professor of Reproductive Biology and Family Planning, and current Interim Chair of Obstetrics and Gynecology at Duke University in Raleigh, North Carolina.
Research Support and Transparency
Funding for this investigation came from the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The research team emphasized that the interpretations and conclusions drawn represent their professional perspectives and may not align with the formal positions of the National Institutes of Health.
The presentation, titled Oral Abstract #8: “Association between SARS-CoV-2 vaccine in pregnancy and child neurodevelopment at 18-30 months,” is slated for publication in the February 2026 edition of PREGNANCY, the prestigious peer-reviewed journal affiliated with the Society for Maternal-Fetal Medicine.
