Health
Prenatal use of acetaminophen is not linked to an increased risk of ADHD or autism, new study suggests
Topline
A new study comparing siblings who were and were not exposed to acetaminophen during pregnancy found that the drug did not increase the risk of autism and ADHD, adding new evidence to a long-debated topic.
A pregnant mother holding her belly.
Key facts
The researchers followed millions of children for 26 years after they were born, and they saw a small increase in ADHD, autism and intellectual disabilities in the overall population compared to when they were younger; approximately 7.5% were exposed to acetaminophen (the active ingredient in Tylenol) during pregnancy.
The risk of developing these neurodevelopmental disorders in children who were not exposed to acetaminophen before birth versus those who were was 1.33% versus 1.53% for autism, 2.46% versus 2.87% for ADHD and 0.70% versus 0.82% for intellectual disabilities. to the study published Tuesday in JAMA Network Open.
However, the researchers decided to also use a sibling model to investigate the risks, because prenatal exposure to acetaminophen was more common in children with parents who smoked was lower during pregnancy social economical status and previous diagnoses of neurodevelopmental disorders disordersall potential risk factors for ADHD and autism.
They found no increased risk when comparing siblings exposed to acetaminophen before birth and those who were not exposed, meaning the increased risk of developing neurodevelopmental disorders may be due to other factors, such as genetics.
Previous research has shown that prenatal use of acetaminophen may increase the risk of neurobehavioral problems, but the current study found no evidence to support a cause-and-effect relationship using a sibling model.
The study’s researchers noted that because siblings share much of the same genetic background and may be exposed to similar environmental factors during pregnancy, comparing siblings – which most previous studies did not do – helps to reduce these keep external factors under control.
Paracetamol is the only painkiller Generally considered safe for use during pregnancy, but many pregnant people may not use acetaminophen because of fears of potentially harmful side effects, so researchers are hopeful that this study will provide “reassurance” to expectant parents.
Crucial quote
“The findings of this study may be welcome news for birthing people who use paracetamol as a pain or fever management option, as there are few safe alternatives available for relief,” said Renee Gardner, study author and principal investigator at Sweden’s Karolinska Institutet, in a thesis.
Large number
2.4 million. That’s how many children – all of whom were born in Sweden – were used as part of this cohort, making this the largest study to date to investigate the link between Tylenol and ADHD, autism and intellectual disability, according to the study.
In return for
The link of acetaminophen to neurodevelopmental disorders is a controversial topic within the health community, as several studies have previously shown that the drug causes an increase in neurobehavioral problems. Children whose cord blood samples contained the highest doses of acetaminophen were about three times as likely to develop ADHD and autism, according to a separate JAMA. study published in 2019. An international group of researchers recommended in 2021 that pregnant people limit their exposure by using the lowest effective dose for the shortest time, and called for more warnings about acetaminophen use during pregnancy, according to research published in Nature Reviews Endocrinology. However, they noted that other factors, such as maternal alcohol use and stress, may also play a role. Long-term acetaminophen use during pregnancy resulted in a 20% higher risk of autism and a 30% higher risk of ADHD, a 2018 study meta-analysis published in the American Journal of Endocrinology.
Important background
A special 2021 study also used a sibling model to investigate this association, and it found that both the exposed and unexposed children of mothers who took acetaminophen during pregnancy had an increased risk of developing ADHD. The researchers concluded that these results may be partly due to “unobserved familial factors.” The Food and Consumer Product Safety Authority said in 2015, the evidence was too ‘limited’ to make recommendations against the use of over-the-counter medications such as paracetamol during pregnancy. A class action lawsuit was filed against the makers of Tylenol and similar generic versions of the drug, in part because of the 2021 Nature article’s recommendations. A federal judge did ruled in December 2023, the research cited in the lawsuit cannot be used as evidence as at least one of the plaintiffs’ experts used “cherry-picked and misrepresented research results and refused to explain the role of genetics in the etiology of either acknowledge. [autism spectrum disorder] or ADHD.” In September 2023, the FDA declined to comment about the lawsuit, although earlier that year it conducted a new review of more recent studies and said they were “limited” and “inconsistent.” Other medical bodies such as the American College of Obstetricians and Gynecologists (ACOG) retain that the use of paracetamol during pregnancy is safe in moderation.
Read further
Federal judge says research cannot be used to link acetaminophen to autism and ADHD (ABC news)
