US President Donald Trump used the presidency platform on Monday to promote an unproven relationship between Tylenol, vaccines and autism without giving new evidence.
Speaking from the White House, Trump said women should not take acetaminophen, which is also known as the brand name Tylenol and “pregnant.” He said the Food and Drug Administration would notify doctors that acetaminophen use could be “incorporated” with an increased risk of autism, but did not immediately provide medical evidence of the FDA's new recommendation.
Trump also raised unfounded concerns about vaccines that contribute to rising autism rates affecting one in 31 US children today, according to the CDC.
Health Secretary Robert F. Kennedy Jr. said Trump's urging him to launch a “doctoral” effort to identify all causes of autism.
Kennedy promised earlier this year to determine the cause of autism by September. There is no single cause, and rhetoric has confusing brain experts who say that decades of science seem to ignore genetic and environmental factors that play a role.
This is what we know about autism.
Autism is not a disease. This is a complex developmental state well known as autism spectrum disorder that affects different people in different ways.
It can include delays in language, learning, or social and emotional skills. For some people, deep autism means being nonverbal and having an intellectual disability, but the majority of people with autism experience far more milder effects.
Autism rates have risen for decades
There are two main reasons. First, the definition of autism has broadened as scientists expanded their understanding of its broad characteristics and symptoms. It has resulted in a change in the criteria physicians use to diagnose autism and improvements in screening.
At the same time, parents increasingly sought diagnosis as autism became more well known and schools began to provide educational services they wanted to help their children.
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In the 1990s, only children with the most severe symptoms were thought to have autism. In the early 2000s, the autism rate was estimated to be one in 150 children as definitions began to change. The most recent count, one in about 31 children, is affected by autism spectrum disorder.
This increase is not one of the profound cases. Boston University expert Helen Tagger Fulsberg said this is a mild increase in cases that have not been historically considered autism.
There is no single test for autism. Autism is diagnosed primarily through developmental and behavioral assessment.
It is difficult to determine whether there are additional factors behind the increase.
What is the status of autism research?
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Science shows that autism is primarily rooted in genetics, with hundreds of genes that play a role. Even if the parent does not show signs of autism, they can inherit these genes even if their brain is developing and their rapidly split cells make a mistake, even if their parents do not show signs of autism.
Experts say that various combinations of genes and other factors can all affect fetal brain development.
What about the environmental impact?
Researchers have identified other factors that can interact with genetic vulnerability to increase the risk of autism. These include the age of the child's father, the age of preterm birth, and whether the mother had certain health issues during pregnancy, such as fever, infection, or diabetes.
Concerns that measles vaccines or other vaccines could be linked to autism have long been exposed by stress scientists and major advocacy groups for people with autism.
The Washington Post reported Monday that the Trump administration plans to link autism to the use of Tylenol, or acetaminophen, a painkiller during pregnancy.
Research has increased the likelihood that taking over-the-counter pain medications during pregnancy could be linked to the risk of autism, according to David Mandel, an autism expert at the University of Pennsylvania.
One big note: Untreated fever during pregnancy, especially early pregnancy, increases the risk of miscarriage, premature birth and other problems, according to the Maternal Fetal Medicine Association.
The Tylenol label advises women to ask doctors about their use in pregnancy, and continues to advise society that it is a suitable option for treating fever and pain during pregnancy.
Last week, Canadian obstetricians and gynecologists said they claimed painkillers are safe after reviewing all the evidence available ahead of the expected announcement in the US.
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