Leucovorin, Tylenol, Other

A Statement from the Society for Developmental and Behavioral Pediatrics On Recent Autism Claims

The Society for Developmental and Behavioral Pediatrics (SDBP) stands with concerned families, scientists, and clinicians in emphasizing that messaging about autism and its causes must be based on clear, unbiased scientific findings. We understand that parents, as well as clinicians and scientists, want more answers about what causes autism, and we're committed to sharing what the research actually tells us.

What We Know About Autism's Causes
Decades of research shows that autism has complex causes involving both genetics and environmental influences working together. Importantly, autism is not caused by anything parents did or did not do. No single factor—whether genetic or environmental—causes autism on its own. Instead, autism likely results from many different genetic variations interacting with environmental factors during critical periods of brain development.

About Recent Claims
Regarding acetaminophen (Tylenol) use during pregnancy: There is no strong evidence showing a direct relationship between the appropriate use of acetaminophen during pregnancy and harmful effects on fetal development. Some recent studies have suggested associations, but these do not prove causation. Importantly, when researchers used more sophisticated study designs that compared siblings within the same family—which better controls for genetic and maternal health factors—any previously observed associations between acetaminophen use and autism disappeared. This suggests that family genetics and maternal health, rather than acetaminophen itself, may explain earlier findings. Acetaminophen continues to be considered safe when used as directed during pregnancy by the American College of Obstetricians and Gynecologists and other leading medical groups.

Regarding folate, folate receptor autoantibodies, and leucovorin treatment: While evidence suggests that getting adequate folate during critical windows of pregnancy may reduce autism risk, appropriate supplementation is already recommended for all pregnant women. Much more research is needed on folate receptor autoantibodies and leucovorin as possible treatments for autism. The research on leucovorin comes from a very limited number of studies of variable quality, each using different doses and measuring different outcomes, making it impossible to draw definitive conclusions. Current folate receptor autoantibody testing (FRAT) is unreliable, and definitive recommendations about leucovorin treatment cannot be made without more rigorous studies.

SDBP Mission Statement: Optimizing the development and behavioral (DB) health of all children and families through interprofessional collaboration.

The Need for Caution and Clarity
Many people are understandably seeking answers and offering explanations for autism's causes and potential treatments. However, we must be cautious before accepting oversimplified answers and unproven treatments. Autism's complexity requires careful, evidence-based approaches rather than quick fixes that may not help and could potentially cause harm. Flawed studies and premature claims can promote false hope in families while also inducing unnecessary parental guilt and fear about decisions made during pregnancy or early childhood. Rigorous epidemiological research (including >20 years of data from the Centers for Disease Control and Prevention) strongly suggests that changes in diagnostic criteria, increased awareness, routine screening and case identification, and increased availability of clinical services are the primary drivers of rising diagnosis rates. Other factors may also play a role, and we need continued funding of well-designed studies to explore how neurobiology, genetics, care access, and other factors contribute to prevalence estimates over time.

Similarly, a robust and growing body of evidence-based supports are known to benefit people on the spectrum, and we need more large, high quality longitudinal studies of treatment and support approaches to guide practice recommendations.

Our Recommendations Children and adults with autism and other disabilities should be valued, not vilified. Stereotypes portraying autistic people as lost causes who cannot contribute to society are both inaccurate and gravely harmful. Unscientific, overly simplistic, and premature assertions about causes and treatments are a distraction from the very real needs of the autism community. We encourage leaders at HHS to partner with expert scientists, clinicians, and the community to support the health and wellbeing of people with autism and other developmental disabilities through evidence-based medical care, mental health supports, and home and community-based services. This includes robust funding for autism research, advocacy for the long-term needs of people with autism throughout their lifespan, expanded access to quality educational and vocational supports, improved employment opportunities, and other supports that help youth and adults with autism and other developmental disabilities thrive in their communities.