In a controversial announcement this week, President Trump and Health and Human Services Secretary Robert F. Kennedy Jr. claimed — without evidence — that there is a link between the use of acetaminophen during pregnancy and autism.
Trump also said pregnant women should only take the medication if they have an "extremely high fever and you feel you can't tough it out, you can't do it."
Alongside the announcement, the Food and Drug Administration said it would be initiating a label change for acetaminophen and sent a letter to doctors warning of "an association" between autism and acetaminophen use in pregnancy.
The letter notes that "a causal relationship has not been established and there are contrary studies in the scientific literature," but says physicians "should consider minimizing the use of acetaminophen during pregnancy."
Experts and major medical organizations, however, strongly disagree with the administration's assertions. And they expressed concern that warning pregnant people not to take acetaminophen, commonly known by the brand name Tylenol, could have dire consequences for both mothers and their babies.
"The headline, very clearly, is that there have been no studies that have definitively shown that Tylenol causes autism," Dr. Natalie Azar, NBC News medical contributor, said during a Sept. 23 segment of The TODAY Show.
"The science is very clear that there's really no causal link between acetaminophen use during pregnancy and autism in children," Dr. Sindhu Srinivas, professor of obstetrics and gynecology at the Perelman School of Medicine at the University of Pennsylvania, tells TODAY.com.
And by pushing patients away from acetaminophen, the administration may "actually be forcing pregnant patients to take riskier options for their health," Dr. Mariana Montes, a former pediatrician and now obstetric anesthesiologist in Illinois and Fellow with Physicians for Reproductive Health, tells TODAY.com.
“Nothing is more important to us than the health and safety of the people who use our products," said Kenvue, the makers of Tylenol, in a statement earlier this month. "We have continuously evaluated the science and continue to believe there is no causal link between acetaminophen use during pregnancy and autism."
Meanwhile, the medication is one of the few safe options that pregnant people have to manage pain and fever, Azar said. And experts have expressed concern that warning pregnant women away from acetaminophen may be dangerous.
Using Tylenol in Pregnancy
For pregnant people experiencing pain or fever, acetaminophen is really the only option. There are no alternatives, Azar said, "which is why we're even having this conversation. There is no safe (alternative) or substitute for Tylenol."
Other common medications, like ibuprofen or Advil, are not recommended during pregnancy, Azar says. And narcotics, like oxycodone, "have their own sort of risks associated with them," says Srinivas, who is also the president of the Society for Maternal Fetal Medicine (SMFM).
"But that doesn't just mean that you use Tylenol liberally," Azar added.
"Acetaminophen has long been established as a safe pain reliever and fever reducer for use during pregnancy," according to the American College of Obstetricians and Gynecologists. But it should only be taken "as needed, in moderation, and after consultation with a doctor," the organization notes.
And keep in mind that acetaminophen isn't just in Tylenol, Dr. Hugh Taylor, professor of obstetrics, gynecology, and reproductive sciences at the Yale School of Medicine, tells TODAY.com. It's also a common ingredient in cold and flu remedies, for instance, "so sometimes you don't even know how much you're getting," he adds.
Untreated Fever and Pain During Pregnancy Can Be Dangerous
One concern with warning people against taking acetaminophen during pregnancy is that they may not have a way of treating severe pain or fever.
Leaving these conditions alone carries "significant maternal and infant health risks," according to the Society for Maternal-Fetal Medicine. "Untreated fever, particularly in the first trimester, increases the risk of miscarriage, birth defects, and premature birth," the organization says. "And untreated pain can lead to maternal depression, anxiety, and high blood pressure."
Using acetaminophen to treat pain and fever while pregnant is safe, the SMFM says.
It’s not always obvious what’s causing a patient’s fever or pain, Srinivas notes, and some potential causes, like infections, can be particularly risky.
For instance, urinary tract infections are common for patients early in pregnancy, Montes says. And a fever may be the first noticeable symptom of the infection. Because a high fever can cause uterine irritability, which can harm the fetus and even lead to miscarriages, it's important to treat the fever, Montes explains.
Back pain is also common during pregnancy, she says, and as long as a patient is staying within the recommended dose of acetaminophen, it's generally safe to use to manage that pain.
“There aren’t any other better alternatives to Tylenol,” Taylor explains. “And, sometimes, there are medical conditions that need treatment, that actually cause harm to the pregnancy, and taking Tylenol is a good way to reduce those risks,” he says.
High fevers for prolonged periods of time can cause developmental abnormalities, Taylor explained, and pain — especially pain so severe that it leaves you immobile — can lead to blood clots, which pregnant people are already at a higher risk for developing.
“I tell my patients to not be afraid of it, but not to take it frivolously,” Taylor says. “Be judicious about it.” And he recommends anyone deciding whether or not to take acetaminophen during a pregnancy check in with their doctor for individual guidance.
The Science on Acetaminophen and Autism
No study has shown conclusively that acetaminophen causes autism, Azar explained, but “the research has shown some inconsistent results.”
While the potential link between acetaminophen exposure and autism is not new, “the science really isn’t settled on this,” Taylor agrees.
A study published this August in the journal Environmental Health suggests there may be a link between exposure to acetaminophen and the development of neurodevelopmental disorders, particularly autism and ADHD.
But other recent studies have come to different conclusions.
A comprehensive review published in the Journal of the American Medical Association last year, for instance, found a small increase in the risk for autism among kids born to mothers who took acetaminophen while pregnant. But after taking the additional step to compare those kids to siblings who weren't exposed to acetaminophen in the womb, the link disappeared.
“We were able to adjust for things that we saw that other people might have missed before,” Brian Lee, associate professor of epidemiology at Drexel University and author of the study, told NBC News earlier this month.
And a 2015 FDA review did not find enough evidence of a link to change the agency’s recommendations at the time.
All studies have their limitations, says Taylor, who was an author on a 2021 statement published in Nature Reviews Endocrinology that expressed concern about the overuse of acetaminophen in pregnancy.
Since that paper was published, "There have been a couple of big papers, but they contradict one another," Taylor says. "So it hasn't clarified the issue to the point where I think we can be definitive about it."
And, because these associations are just correlations, it's challenging to know how to interpret the results. "What caused the problem might not have been the Tylenol," Taylor says. "It may have been the underlying condition for which they were taking the Tylenol," he explains.
The studies "don't really take into account why people were taking acetaminophen," Srinivas agrees. If someone had a high fever due to a viral illness, that could have also led to an increased risk for preterm birth or babies having higher heart rates, she says, "and all of those things can be associated potentially with the neurodevelopmental outcome."
In the aftermath of Trump's statements, major medical organizations have reaffirmed the safety and important uses for acetaminophen during pregnancy. So far, the organizations say they won't be changing their recommendations on Tylenol.
In a statement, ACOG said the comments linking acetaminophen to autism were "highly concerning to clinicians, but also irresponsible when considering the harmful and confusing message they send to pregnant patients, including those who may need to rely on this beneficial medicine during pregnancy."
The statement continued, “In more than two decades of research on the use of acetaminophen in pregnancy, not a single reputable study has successfully concluded that the use of acetaminophen in any trimester of pregnancy causes neurodevelopmental disorders in children."
The SMFM agrees, saying in a statement that the organization "stands behind our recommendation that acetaminophen use during pregnancy has not been shown to cause or increase the risk of autism or other neurobehavioral problems in children."
And, Azar noted, autism is a multifactorial disorder, meaning experts believe it may develop due to a combination of things like genetic risks, environmental exposures and more.
"Trying to tease out or pinpoint a singular cause, you really can't do that," Azar said. And Taylor agrees: "Autism is a complex disease. There's probably not any one single cause," he says.
"Does this have some contribution to it? We don't know, so let's be let's be cautious until we know for sure," Taylor added.
If You're Feeling Confused or Anxious About Tylenol Use, Talk to Your Doctor
Knowing that there is likely a lot of anxiety, panic and guilt among people who are pregnant or trying to become pregnant in the wake of the announcements this week, Srinivas wants to encourage people to have open conversations with their doctors about what they're feeling.
"There's a lot of guilt associated with taking any medication in pregnancy," Srinivas says. "And as a maternal-fetal medicine specialist, I have this conversation all the time with patients who need to be on medicines (such as antidepressants) for a variety of medical conditions."
Her main message to patients is: "You need a healthy mom to have a healthy pregnancy," she says.
Montes agrees, adding that she's concerned the Trump administration's announcement will make patients feel too ashamed to discuss acetaminophen with their doctor, or like they have to simply endure the pain to prevent serious outcomes for their baby.
"In no scenario would I ever recommend to a patient to 'tough it out,'" she says, referring to President Trump's exact words. "You do not 'tough out' an infection. You do not 'tough out' back pain."
That mindset sets patients up to think "that they must tough it out in order for them to have a healthy fetus or a healthy pregnancy, and that's actually false," Montes says.
That's why it's so important to treat conditions as they need to be treated — even and especially during pregnancy, Srinivas adds. "The absence of treating them is also very harmful."
