January 10, 2024
Kristoffer Tripplaar/Sipa USA
A new study suggests children of mothers who take Tylenol during pregnancy may experience delayed language skills in early childhood. The drug is considered safe, but more research is needed, according to the study's authors.
Tylenol has long been recommended as the safest painkiller that pregnant women can take, but research has raised questions in recent years about whether the over-the-counter drug could be harmful to developing babies.
A new study from the University of Illinois Urbana-Champagne suggests pregnant women who take acetaminophen, which is sold under the brand name Tylenol, could see their child experience delayed language abilities.
Researchers looked at 2-year-olds and 3-year-olds who were part of the Illinois Kids Development Study, which examines how exposures to chemicals during pregnancy influence child development. The mothers of these children had been surveyed about their Tylenol use every 4-6 weeks during their pregnancies and were again surveyed after they gave birth. The study included 298 2-year-olds and then reassessed 254 of them who returned at age 3, when parents were asked to compare their kids' language skills to their peers.
The researchers found that a mother's Tylenol use during the second and third trimesters was linked to modest but significant delays in their child's early language development.
"We found that increased use of acetaminophen — especially during the third trimester — was associated with smaller vocabulary scores and shorter 'mean length of utterance' at 2 years," said Megan Woodbury, a graduate student who served as one of the study's lead researchers.
For each time mothers took Tylenol during the third trimester, 2-year-olds showed an average reduction of nearly two words in their vocabularies.
"This suggests that if a pregnant person took acetaminophen 13 times — or once per week — during the third trimester of that pregnancy, their child might express 26 fewer words at age 2 than other children that age," Woodbury said.
Notably, among parents who brought their kids back a year later, the study also found that Tylenol use during the third trimester was tied to more unfavorable peer comparisons of their kids' language abilities. This was more common among boys, the researchers said.
The researchers acknowledged that further studies need to be done with larger groups of kids to better understand what's behind these results. They said pregnant women should not be afraid to take Tylenol if they have severe pain or a fever, which can be dangerous for mothers and babies.
Still, the study adds to questions raised by past research into the safety of Tylenol when taken during pregnancy.
A 2018 study from the Icahn School of Medicine at Mount Sinai focused on Tylenol use during early pregnancy, between weeks 8-13. That study noted about 65% of pregnant American women use Tylenol, citing estimates from the U.S. Centers for Disease Control & Prevention.
The Icahn School researchers found that 10% of children in their study showed delayed language abilities, with longer periods of communication deficits observed among boys. But girls born to mothers who took Tylenol more than six times in early pregnancy were almost six times more likely to have language delays than girls whose mothers didn't take the drug.
Other studies have suggested Tylenol use during pregnancy could be linked to decreased IQ scores among 5-year-olds and possibly a heightened risk of developing sleep disturbance, memory problems and attention deficit hyperactivity disorder.
The Illinois researchers said it's possible that Tylenol use during the second and third trimesters impacts fetal brain development, including hearing and language skills that begin forming before birth.
The emerging research has sparked concern because acetaminophen is considered safer than ibuprofen for pregnant woman, and Advil and other anti-inflammatory drugs have been linked to a range of fetal complications.
Some experts contend additional research needs to be done before advising against Tylenol use during pregnancy. The reasons acetaminophen may be impacting developing babies is still unclear. It's possible that the underlying issues causing mothers to take Tylenol are a better explanation for the developmental changes seen in their kids.
"I would argue that in the absence of a plausible mechanism for acetaminophen causing problems with language development, it is more likely that infection or inflammation — entities for which acetaminophen is often administered, as the authors themselves point out — could better explain changes in the vulnerable prenatal brain that, in turn, could lead to language problems," Dr. Carl Baum, a professor of pediatrics at the Yale School of Medicine, told Medical News Today about the Illinois study, which was published in the journal Pediatric Research.
Susan Schantz, one of the lead researchers of the Illinois study, said pregnant women don't need to avoid Tylenol altogether. They should instead consider more carefully when and why they are using it.
"There aren’t other options for people to take when they really need them," Schantz said. "But perhaps people should use more caution when turning to the drug to treat minor aches and pains."
