Jan 17, 2026
3 min read
Taking Tylenol during pregnancy does not increase the risk of autism in children, a major new review has found, contradicting the opinions of Trump and Kennedy.
"Don't take Tylenol. Don't take it. Try your best not to take it."
That was the message from President Donald Trump when he and Health Secretary Robert F. Kennedy Jr.announced in September that women should avoid Tylenol during pregnancy because of what they described as a link to autism.
The risk was not supported by reliable scientific evidence when Trump issued the warning.Now a group of researchers have responded with perhaps the most thorough study of science on the subject.
Their review, published Friday in the medical journal The Lancet Obstetrics, Gynecology, & Women's Health, found no link between pregnancy and acetaminophen, also known as paracetamol, the active ingredient in Tylenol, which is used to treat autism, attention-deficit/hyperactivity disorder or intellectual disability.
The authors said they conducted the study in part to clear up confusion following Trump's announcement, as untreated fevers can pose health risks to mothers and children.
Dr. Francesco Antonio, one of the authors of the article and professor of fetal medicine at Chittagong University in Italy, said: "After this announcement, many mothers are actually afraid to take paracetamol."
The report's main conclusion is that acetaminophen is safe during pregnancy, according to Dr Asma Khalil, another of the paper's authors and a consultant obstetrician and fetal medicine specialist at St George's Hospital in London.
"It remains the first-line therapy we would recommend when pregnant women experience pain or fever," she told reporters.
In a press release, Lanset called the paper a standard evidence review.
The "gold standard" description echoes language used by Kennedy, including in September, when he said the National Institutes of Health would conduct "impartial, non-political, gold-standard scientific research and academic freedom" in research into the causes of autism.
Four researchers who were not involved in the new paper praised its rigor.
"I don't think there's a better way to look at the data than this Lancet article," said David Mandell, a professor of psychiatry at the University of Pennsylvania.
The seven-member team behind the new paper, based in England, Italy and Sweden, used three methods to evaluate the studies published in September.
First, they excluded studies that did not compare pregnancies in which Tylenol was used with those without it, as well as studies that did not disclose the health histories of the pregnant women or what medications they were taking.They also did not include studies that asked women to self-report whether they had taken Tylenol and whether their child had autism.Instead, the researchers relied only on studies that used medical records or questionnaires administered or reviewed by a health care professional.Out of thousands of studies, 43 prey
Next, the researchers evaluated the studies based on their quality and the existence of factors that could bias the results.They did not include those of poor quality, such as those that did not follow study participants for a long time or those that did not clearly describe health outcomes.
Finally, they conducted two rigorous studies of Tylenol use and autism, each comparing large groups of siblings—one that was exposed to Tylenol in the stomach and the other that was not.Siblings shared genetics and grew up in the same neighborhood, with similar levels of wealth and education, so the researchers could assume that these factors did not affect the results of the study.
All three methods reached the same conclusion: no association between Tylenol use during pregnancy and neurodevelopmental disorders.
"No matter how you analyze it, we found that acetaminophen does not cause ADHD, autism or intellectual disability," Mandell said.
When asked about the findings, the director of the Department of Health and Human Services said the analysis does not resolve the question of whether Tylenol use affects mental health.The director accused the authors of the findings of failing to include evidence and creating studies that were biased by the lack of cooperation in teaching.
“According to HHS, many experts have expressed concern about the use of acetaminophen during pregnancy,” said Andrew Nixon, a spokesman for the department.
Nixon, specifically the Harvard T. Chan School of Public Health, whose review, published last year in the journal Environmental Health, found a link between autism and Tylenol use during pregnancy.The Trump administration cited the results as evidence of Tylenol's dangers.Baccarelli did not respond to a request for comment.
Khalil said Baccarelli's review and other small studies that found such associations likely did not do enough to rule out confounding.
Mandell also said that Baccarelli's review did not go through as many factors as the new analysis.
"At least, it gives the impression of reckless hunting," he said.
In the months since his initial statements about Tylenol, Trump has doubled down, writing to Truth Social earlier this month: "Pregnant women, do not use Tylenol unless absolutely necessary."
However, a written warning sent by the Food and Drug Administration to doctors - announced by Trump and Kennedy in September - simply asked them to "consider reducing the use of acetaminophen."The warning added that the drug is still the safest over-the-counter option for reducing pain and fever during pregnancy and that the supposed link between Tylenol and autism is "an ongoing area of scientific debate."It has been said
Autism researchers say there is no need to discuss this issue.
"The question is answered," said Alicia Halldii, major scientific officer in the Autiles's science would not involved in the new job."It was never a connection between acetaminofen and autism. We can keep talking about it now and focus on what causes iztism instead of confusing families and continue to blame the mother."
