Some of the top Ivy League universities, scientists, and the FDA responded to the link between autism and Tylenol (acetaminophen) use during pregnancy.
It has become a controversial topic ever since U.S. President Trump recently brought it up in a White House address.
In mid-September of 2025, Trump and Secretary Robert F. Kennedy Jr. issued an FDA warning for doctors in America not to recommend its use for pregnant women because of an alleged link to autism.
Yale School of Public Health finding
Dr. Zeyan Liew, an Associate Professor of the Yale School of Public Health, has spent years investigating contributors to neurodevelopmental disorders. Dr. Liew stated that there is “no proven causal relationship between acetaminophen use and autism.”
Several large observational studies have reported “associations” between frequent or prolonged acetaminophen use during pregnancy and higher rates of neurodevelopmental disorders in children.
Experts emphasize that these studies are “not conclusive.” Instead, there are “other factors” such as underlying illnesses or genetic predisposition that might play a role in the development of autism.
Harvard Study by Dean Andrea Baccarelli
The Harvard study was published recently in “BMC Environmental Health.” Harvard Dean Andrea Baccarelli, who is a health and professor of environmental health, was the senior author of this study.
In this study, researchers analyzed results from 46 previous studies worldwide that investigated the potential link between prenatal acetaminophen use and subsequent NDDs (neurodevelopmental disorders) in children.
The researchers noted that “while steps should be taken to limit acetaminophen use, the drug is important for treating pain and fever during pregnancy, which can also harm the developing fetus.”
According to Science Daily, the findings were as follows: High fever can raise the risk of neural tube defects and preterm birth. “We recommend judicious acetaminophen use — lowest effective dose, shortest duration — under medical guidance, tailored to individual risk-benefit assessments, rather than a broad limitation,” they wrote.
In late September, the Food and Drug Administration (FDA) announced that it would issue a letter to clinicians urging them to be cautious about the use of acetaminophen (Tylenol) in pregnancy.
Baccarelli discussed his study with Health and Human Services Secretary Robert F. Kennedy Jr. in the weeks leading up to that announcement and provided the White House team with an statement noting his research found “evidence of an association” between prenatal exposure to acetaminophen and neurodevelopmental disorders.
“That association is strongest when acetaminophen is taken for four weeks or longer,” Baccarelli said.
While Baccarelli agrees that further research is needed to confirm this association and link, he is a firm believer that based on existing evidence that “there should be caution about acetaminophen use during pregnancy (especially heavy or prolonged use) i warranted.”
FDA responds to this study
FDA Commissioner Marty Makary stated that “The FDA is taking action to make parents and doctors aware of a considerable body of evidence about potential risks associated with acetaminophen.”
Dr. Makary continued, “Even with this body of evidence, the choice still belongs with parents. The precautionary principle may lead many to avoid using acetaminophen during pregnancy, especially since most low-grade fevers don’t require treatment.”
“It remains reasonable, however, for pregnant women to use acetaminophen in certain scenarios,” he acknowledged.
Evidence in recent years in cohort studies in Nurses’ Health Study II and the Boston Birth Cohort have “suggested a correlation between acetaminophen use during pregnancy and subsequent diagnosis of conditions like autism and ADHD.”
Some of these studies have described that the risk may be most pronounced when acetaminophen is taken “chronically” throughout pregnancy.
Tylenol maker Kenvue responds that taking acetaminophen ‘does not’ cause autism
According to the BBC, Tylenol maker Kenvue revealed that “science clearly shows that taking acetaminophen does not cause autism.”
Dr. Evan Schrader responds to the link between autism and Tylenol use during pregnancy
OB/GYN physician Dr. Evan Schrader, who delivers babies on a daily basis in Florida, stated, “I think it’s sad that individuals with social and political impact are spreading misinformation because it ultimately hurts patients and undermines the sacrifice and training of true experts.”
Dr. Schrader continued, “Research is a complex and vetted process, and misinterpreting that research needs to be honored and left to medical professionals who have dedicated their lives to bettering life for others — so go talk to your doctor to get the best recommendations for your individualized healthcare needs.”
“If I must say it again — Tylenol has not ever been shown to have a causative effect on autism and pregnant women and children should continue using this very safe medication when it’s indicated,” Dr. Schrader elaborated.
Nurse Jamie Prevatt reacts to the Tylenol during pregnancy debate
Nurse Jamie Prevatt, RN, who has been a nurse for over 33 years in the United States, stated, “My thoughts on Tylenol and pregnancy my entire nursing career is that it was the No. 1 drug of choice for women during pregnancy.”
“It’s the only drug that you could take safe safely,” Prevatt said. “If you have any doubts, I would encourage you to open a dialogue with your physician, and discuss it at length if you want to do some research of her own, choose the studies they have the most participants as those are the ones that are more reliable; the more participants, the more accurate they are.”
Conclusion
All in all, more definitive research needs to be done on this topic. In the meantime, the U.S. Food and Drug Administration (FDA) and the CDC continue to recommend acetaminophen as the safest over-the-counter pain reliever for women that are pregnant.
