Research Challenges Claims Linking Tylenol Use to Autism Risk

In September 2022, President Donald Trump claimed that taking Tylenol during pregnancy might be linked with an increased risk of autism. This assertion generated a wave of inquiries from patients to healthcare providers, prompting a swift response from the medical community. Dr. Nathaniel DeNicola, an obstetrician-gynecologist based in Newport Beach, California, noted that the public concern faded quickly as experts reassured patients about the safety of acetaminophen use in pregnancy.

DeNicola, who contributed to the guidelines from the American College of Obstetricians and Gynecologists (ACOG), emphasized the importance of expert guidance. “The scientific medical community was prompt in its response,” he stated. “Patients are going to their doctors, and the public seems to trust the experts.”

Similarly, Dr. Lynn Yee, a maternal-fetal medicine specialist at Northwestern University Feinberg School of Medicine, observed a decline in patient anxiety regarding Tylenol use. “In the fall, there was significant concern, but by January, fewer patients were asking about it,” she explained. Yee praised professional organizations for effectively communicating the message that acetaminophen remains a safe choice for managing pain and fever during pregnancy.

Understanding the Risks and Benefits of Acetaminophen

Experts stress that autism is a multifaceted condition influenced by various factors, including genetics and environmental exposures. The scientific debate regarding the relationship between acetaminophen and autism is ongoing. Following Trump’s claims, ACOG reaffirmed that acetaminophen is the preferred analgesic during pregnancy, advising its judicious use in consultation with healthcare professionals.

Acetaminophen, also known as paracetamol and marketed under the brand name Tylenol, is widely regarded as the only safe over-the-counter medication for pain or fever during pregnancy. Other common pain relievers, such as ibuprofen or regular-dose aspirin, can lead to complications.

The risks of untreated fevers during pregnancy are significant. Experts warn that failing to manage a fever can jeopardize the health of both the mother and the fetus. “Untreated fevers can have short- and long-term impacts on fetal neurodevelopment,” Yee added. “We do not have better, safe alternatives for reducing fevers during pregnancy.”

Data indicates that approximately 65% of pregnant women use acetaminophen at some point during their pregnancy.

The political implications of the Tylenol discourse were underscored when the White House issued a fact sheet in September 2022. This document referenced studies suggesting that acetaminophen use, particularly in the later stages of pregnancy, might be associated with long-term neurological effects in children, including autism and ADHD. In response, the U.S. Food and Drug Administration (FDA) advised clinicians to minimize acetaminophen use during pregnancy for routine low-grade fevers.

One of the studies cited by the Trump administration was a comprehensive analysis published in August 2022 in the journal BMC Environmental Health. This review examined 46 previous studies and suggested a link between acetaminophen exposure during pregnancy and increased instances of neurodevelopmental disorders. Dr. Andrea Baccarelli, senior author of the study and dean at the Harvard T.H. Chan School of Public Health, noted that the association was most pronounced when the medication was taken for four weeks or longer.

Baccarelli emphasized the need for a balanced approach in recommending acetaminophen use, acknowledging its importance as the only approved medication for pain and fever reduction during pregnancy.

New Research Offers Reassurance

Recent research published in The Lancet Obstetrics, Gynaecology & Women’s Health challenges previous claims, finding no evidence that children born to mothers who used acetaminophen during pregnancy are at an increased risk for autism. The study reviewed 43 published studies involving over 300,000 pregnancies and included a meta-analysis of 17 studies.

Lead author Dr. Asma Khalil, a consultant obstetrician and fetal medicine specialist at St George’s Hospital in London, reported that their findings did not support a link between acetaminophen use and risks of autism, ADHD, or intellectual disabilities in children. The U.S. Department of Health and Human Services acknowledged that while this new paper does not resolve all questions regarding Tylenol’s potential risks, it provides a significant contribution to ongoing discussions.

In response to scrutiny, Khalil stated that the review systematically evaluated all relevant studies and prioritized those least affected by bias. “This review provides reassurance rather than alarm,” she noted, reinforcing that acetaminophen remains an appropriate first-line treatment for pain and fever in pregnancy when used correctly.

Dr. Steven Kapp, a senior lecturer in psychology at the University of Portsmouth, praised the methodological rigor of the new research. He highlighted the importance of sibling-comparison studies, which account for shared genetic and environmental factors.

Kapp argued that these findings suggest society should focus less on seeking preventable causes of developmental disabilities and more on enhancing the quality of life for individuals with disabilities.

DeNicola acknowledged the value of the new research but also pointed out the limited number of sibling studies thus far. “Having only three sibling studies raises questions about the breadth of the evidence,” he said. However, given that these studies consistently support the safety of Tylenol, he believes the findings are reassuring.

As discussions around acetaminophen continue, the medical community remains committed to educating patients about the safe use of medications during pregnancy. Khalil concluded, “It is crucial to communicate that it is safe to use paracetamol when needed, in the right dose for the right duration.”