MINNEAPOLIS — Use of the antiseizure drug valproate by fathers before conception is not associated with neurodevelopmental disorders like autism or attention-deficit/hyperactivity disorder (ADHD) in their children, according to a new study published August 19, 2026, in Neurology® , an official journal of the American Academy of Neurology . The study also found no association with malformations at birth, commonly called birth defects. Researchers note that more studies are needed.
Valproate is a commonly prescribed antiseizure medication. It has been linked to birth defects and developmental problems in babies when taken by mothers, so it is not recommended for those who may become pregnant.
"People with epilepsy need long-term treatment to control seizures, including during their reproductive years," said study author Shi-Heng Wang, PhD, of National Health Research Institutes in Zhunan, Taiwan. "While such drugs have been extensively studied in mothers, less is known about use of these drugs by fathers. Previous studies have found valproate use by mothers is associated with an increased risk of neurodevelopmental disorders and malformations at birth in their children. However, our results show no association with use by fathers."
For the study, researchers looked at the Taiwan National Health Insurance Research Database to identify 2,583,503 children born during a 15-year period. A total of 1,701 children had fathers who took valproate three months prior to conception, during sperm development. The participants were followed for an average of 12 years to see whether they developed any of the disorders.
Of all participants, 1.6% were diagnosed with autism, 7.7% with ADHD, 1.5% with tic disorders, 1.1% with intellectual disability and 3.7% with malformations at birth.
Of those whose fathers took valproate, 1.9% were diagnosed with autism, 10.2% with ADHD, 1.4% with tic disorders, 1.5% with intellectual disability and 3.9% with malformations at birth.
After adjusting for factors like sex, birth weight, maternal and paternal age, pregnancy complications and a maternal history of epilepsy and psychiatric disorders, researchers found no association with valproate use by fathers and increased risk of disorders or malformations in their children.
Researchers then compared siblings. There were 548 sibling sets, children who were exposed to valproate through their fathers, and their full siblings who were not exposed because the fathers were not taking valproate in the three months prior to conception. Researchers found no association between valproate use and the risk of disorders or malformations.
Researchers also looked at other commonly used antiseizure drugs and found no associations.
"A recent warning in the United Kingdom advised against the use of valproate in men 55 and younger due to concerns about adverse outcomes in their offspring, based on the results of European-based studies," said Wang. "But there has been a need for more data. Our study of 2.5 million births in Taiwan adds to the evidence. It found no increased risk of disorders or malformations among children of fathers prescribed valproate or other antiseizure medications. More research is needed before drawing conclusions about changes to current prescribing practices for antiseizure medications."
A limitation of the study was that the follow-up time was shorter for some participants, as little as five years, so it may not have captured the diagnoses of all neurodevelopmental disorders. Future studies are needed that follow children over longer periods of time.
The study was supported by the National Science and Technology Council of Taiwan, Chang Gung Memorial Hospital and the Taiwanese Ministry of Education.
Discover more about epilepsy at Brain & Life® , from the American Academy of Neurology. This resource also offers a website, podcast, and books that connect patients, caregivers and anyone interested in brain health with the most trusted information, straight from the world's leading experts in brain health. Follow Brain & Life on Facebook , X , and Instagram .
The American Academy of Neurology is the leading voice in brain health. As the world's largest association of neurologists and neuroscience professionals with more than 44,000 members, the AAN provides access to the latest news, science and research affecting neurology for patients, caregivers, physicians and professionals alike. The AAN's mission is to enhance member career fulfillment and promote brain health for all. A neurologist is a doctor who specializes in the diagnosis, care and treatment of brain, spinal cord and nervous system diseases such as Alzheimer's disease, stroke, concussion, epilepsy, Parkinson's disease, multiple sclerosis, headache and migraine.
Explore the latest in neurological disease and brain health, from the minds at the AAN at AAN.com or find us on Facebook , X , Instagram
