Should pregnant women avoid paracetamol, as Trump says?

The American president did not hold back at the press conference in the White House on Monday evening, joined by Secretary of Health Robert F. Kennedy Jr.

"Acetaminophen ... can be associated with a very increased risk of autism. So taking Tylenol is not good," Trump said from the podium.

Acetaminophen is the pain-relieving active ingredient that we know as paracetamol. And Tylenol is an American brand name for tablets with this substance.

The FDA, which is responsible for safe food and medicines in the USA, is now preparing to add warnings on products containing paracetamol and inform doctors and the general public, according to a press release from HHS. 

But should pregnant women really stop using paracetamol if they need it?

"Unnecessary fear"

"No," says Hedvig Marie Egeland Nordeng.

She is a professor at the University of Oslo's Department of Pharmacy, and researches medication use during pregnancy.

"Such statements create a lot of unnecessary fear. Paracetamol is what we consider the safest choice when treatment for pain and fever is needed during pregnancy. I would rather ask: What is the risk of not treating? And what are better alternatives?" she says.

We will come back to the answer to that. But first, to some of the other questions probably swirling in many people’s heads following the press conference.

Link between paracetamol and autism?

According to Nature News, which has spoken with several researchers in the field, there are studies showing a link between paracetamol and autism. 

In August this year, a research summary was published in which some researchers concluded that there was a link to developmental disorders such as autism and ADHD. 

But in another review from February 2025, researchers concluded the opposite – that it's unlikely that paracetamol increases the risk of such disorders.

Nordeng confirms that there are studies with conflicting results.

"The point is that you can't pick out individual studies that fit with what you believe. You have to look at all the evidence," she tells Science Norway.

"In 2019, the European Medicines Agency (EMA) reviewed all available research on the use of paracetamol in pregnancy and the risk of developmental disorders in the child," she says.

"They concluded that the observational studies were unclear and could not support any link between the mother's use of paracetamol and developmental disorders," she says.

The American health authorities write more or less the same in the press release that accompanied the White House press conference. This does not align with Trump's claims.

Different studies give different answers

It's very difficult to determine whether such a link exists, Viktor Ahlqvist at the Karolinska Institute in Sweden tells Nature News.

Most research is observational, tracking pregnant women’s medicine use and comparing outcomes for their children. But such studies give uncertain results, says the Swedish researcher.

Nature News writes that the studies are often based on prescription data or information mothers provide about how much medicine they used. But do they remember correctly? And did they actually take the pills they were prescribed?

"All studies have weaknesses. That's why it's so important to look at the big picture," says Nordeng.

If a study shows a correlation – does that mean paracetamol causes autism?

A single observational study can never determine what causes what, nor establish causal relationships.

It may be the mother's health or genes – not the medications – that create the risk of developmental disorders in the child.

There are studies that try to remove as many of these confounding factors as possible by comparing sibling pairs. Siblings share half of their genes, developed in the same womb, and grow up in the same environment.

Both Japanese and Swedish researchers have compared sibling pairs, where one sibling was exposed to paracetamol and the other was not. None of these studies found any increased risk of autism among those exposed, writes Nature News.

This means that what appears to be correlations in some studies may in reality be due to other factors.

"I believe that as of today there is no causal relationship between paracetamol and autism," says Nordeng.

Is increased risk high risk?

Even if future research were to find some actual increase in risk, that does not necessarily mean it's a high risk.

This can be illustrated by one of the largest studies in the field, a study of almost 2.5 million Swedish children, born between 1995 and 2019.

The researchers had information about paracetamol prescribed to the mothers and self-reported use of over-the-counter tablets. They then compared children exposed to paracetamol in the womb with children who were not.

The results showed that 1.42 per cent of the exposed children developed autism, compared to 1.33 per cent of unexposed children. In other words, an absolute risk increase of less than 0.1 per cent.

This is a very small difference, Viktor Ahlqvist, who led the study, tells Nature News. 

Put another way: If we actually were to find a causal link, a very large number of pregnant women would need to take paracetamol for one extra child with autism to be born.

Is it still safest to avoid taking paracetamol?

"Don't take it! Fight like hell not to take it," the American president said at the press conference.

Is he right?

"No, absolutely not," says Nordeng.

She emphasises that it's just as important to consider the risks of not treating the mother's health problems, and what alternatives exist.

Studies show, for example, that fever during pregnancy in itself is linked to an increased risk of developmental disorders in the child. 

"Many health problems, such as high fever, epileptic seizures, severe asthma, and infections increase the risk of complications in pregnancy," says Nordeng. "Ensuring that the mother is as healthy as possible is good for the foetus."

Alternatives are often worse

Other painkillers, such as NSAIDs (ibuprofen, naproxen), are often worse alternatives than paracetamol, says Nordeng.

"NSAIDs should be avoided after week 20 of pregnancy because they can harm the foetus' kidneys. Later in pregnancy, they can affect the baby's heart and breathing, and right before birth, they can increase the risk of bleeding and slow down labour," she says.

Stronger painkillers such as opioids should also be reserved for short-term treatment of severe pain, according to the professor.

"If in doubt, ask a pharmacist or your doctor. Follow the national guidelines in Norway, use common sense, and don't stop taking your medications without discussing it with your doctor. Cutting out medicines you need is neither good for you nor your child," says Nordeng.

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Translated by Alette Bjordal Gjellesvik

Read the Norwegian version of this article on forskning.no

Related content:

Autism rates are rising. Researchers say it cannot solely be explained by more people being diagnosed

Significant rise in ADHD and autism diagnoses in Norway

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