There appears to be a global divide in autism.

The United States is currently experiencing a significant increase in autism cases, with one in every 31 children reported to have the condition. This represents one of the highest rates globally and reflects a substantial rise from one in 150 children in 2000.

In contrast, countries such as France and Germany are reporting much lower rates, with around one in 100 cases. Meanwhile, in Sweden, the rate is about seven in 1,000 children. The gap is not as pronounced in Canada and the UK, where the rate is approximately one in 50.

Experts have explained to the Daily Mail that this discrepancy is mostly due to variations in how autism is defined and diagnosed, as well as a more accepting attitude towards autism in the US. This perspective differs from the explanations given by Health Secretary Robert F Kennedy Jr and President Donald Trump, who point to factors like medications or environmental pollutants.

On Monday, the president and senior health officials claimed in a press conference that expectant mothers should not take Tylenol, or acetaminophen, saying the drug raised the risk of their children being diagnosed with autism.

Yet the experts did say this wasn’t the whole picture, with some suggesting America’s higher obesity rate and now fading drug epidemic was playing a role. 

Its growing population of older mothers, with pregnancy over 30 linked to a higher risk of autism, may also play a role. 

Dr Jeff Singer, a senior fellow at the Cato Institute in the Department of Health Policy Studies, told this website: ‘There is no reason why people in the UK or Canada or Australia are going to be any different to the US.

‘A lot of it has to do with the way medicine is practiced and the different health systems that have been put in place.’

Donald Trump claimed at a press conference yesterday that Tylenol, acetaminophen, can raise the risk of autism if a pregnant women takes it

In a wide-ranging question and answer session, Trump also commented on the apparent divide in rates between America and other countries, telling reporters: ‘I hear Cuba doesn’t have it [Tylenol] because it is very expensive. They don’t have Tylenol, and I hear they have essentially no autism.’

A 2022 study suggested Cuba has an autism rate of 2 to 4 per 10,000 in some settings. Experts caution, however, that these figures likely reflect an under-diagnosis because of limited surveillance in the country. The active drug in Tylenol, acetaminophen, known locally as paracetamol, is available in the country and recommended to pregnant women, although it can often be in short supply.

Autism is a neurodevelopmental condition that affects how a person communicates, interacts with others, and experiences the world.

In the 1970s, the only people diagnosed with the condition were those who had severe communication difficulties, often struggling to speak and interact with others.

But in recent years, the definition has been broadened to include restricted interests, repetitive behaviors and challenges with reading social cues.

Amid the shift, many countries have recorded a rise in autism rates, and boys tend to be at least twice as likely to be diagnosed with the condition as girls.

But experts point out that the uptick has been more pronounced in the US, which also now uses an even broader definition of autism than Europe.

In Europe, most countries use the ICD-11 definition, which is more restrictive and requires, for example, patients to have both unusually persistent problems with social interaction and a range of repetitive, inflexible patterns of behavior.

But in the US, doctors use the DSM-5 system, that is much looser and would diagnose a patient with autism if they had only one of those behaviors.

The result, said Dr Singer, is that it is possible that children diagnosed with autism in the US may well never have been diagnosed with it if they lived in Europe.

The US also has much stricter screening for autism, with American children funneled through an extensive safety net, with teachers, school counselors and pediatricians all routinely checkING for signs of the condition. 

The American Academy of Pediatrics recommends that all children be screened for autism at age 18 and 24 months. 

In many European countries, however, experts say the monitoring is not as tight and there are fewer opportunities to catch children who may be on the spectrum.

Neither the UK, Germany or France have universal screening guidelines in place for autism, with British doctors told only to have children checked for the condition if concerns are raised by parents.

Experts also pointed to divides between the US and broader European population to potentially explain the different rates of autism.

America has a much higher obesity rate, at 40 percent of adults, compared to European countries, with it being 26 percent in the UK, 20 percent in Germany and 17 percent in France.

And this has carried over into pregnant women, with a 2024 study estimating 18.7 percent of pregnant women were obese in North America compared to 12.1 percent in Europe.

Obesity during pregnancy is already known to raise the risk of stillbirths and heart defects in babies. It also raises the risk of gestational diabetes in mothers, which may also cause infants to have an enlarged heart or experience problems during birth.

Trump is pictured above during the press conference yesterday

But studies have also drawn a link between having an obese mother and a child being more likely to develop autism. A 2024 paper from Australia, for example, warned that mothers who were obese during pregnancy had twice the risk of having a child with autism compared to those who were not obese.

Dr Randa Jaafar, a pain specialist in New York City, said: ‘Obesity influences how the brain develops and the blood sugar regulation as well. If blood sugar is high, even if it hasn’t tipped over into diabetes yet, that could all affect the infant’s brain.’

Some experts also suggested to Daily Mail that rising maternal ages could be behind the higher rates of autism in young adults.

Several studies have already linked pregnancy after 30 to a higher risk of autism in an infant, with those who have a baby after age 40 said to have an up to 81 percent higher risk of having a child with autism compared to mothers in their late 20s.

It isn’t clear why this is the case, but scientists have suggested this may be linked to the added time meaning mothers have been exposed to more environmental toxins, like pollutants or heavy metals, that could damage DNA in the egg cell raising the risk.

Dr Singer said: ‘We’ve known for decades that in the mid-30s there is a much greater risk of chromosomal abnormalities and autism, particularly in women over 35. In the US, in 2023, one in five pregnancies were women over 35, that has got to play a role.’

Data does suggest, however, that both American and European mothers are becoming older at roughly the same rate.

In the US, women aged 30 to 39 years account for the largest share of births, at 47 percent of all live births, while four percent of births are to women aged 40 years and over.

In the EU, for comparison, estimates suggest that over half of births were to women aged 30 years and older while about six percent of births were to women aged 40 years and older.

Experts pushed back on claims that taking Tylenol, or acetaminophen, was raising the risks of autism in children, however.

The drugs are widely used on both sides of the Atlantic, known as paracetamol in the UK, and a number of studies have suggested a link between the two conditions. But others have also claimed there is no connection.

Dr Singer said: ‘This is a reasonable question to ask. We know that there are many substances that can cause issues during pregnancy; no one is denying that.

‘American experts surveyed the literature and they pointed out that everything was a trade-off; a high fever during pregnancy is also risky.

‘I would say that it is unhelpful to have the federal government weight in on this. We are on this, we are investigating, my message to politicians is please for them to not get involved.’