Acetaminophen in Pregnancy and Child's ADHD Risk
Risk increases with longer use, researchers say; experts caution the finding needs verification
The maker of Tylenol, McNeil Consumer Healthcare, said in a statement that the medication's label directs women who are pregnant or breast-feeding to consult with a health care professional before using the product.
"Tylenol has more than 50 years of clinical use to support its safety and efficacy and, when used as directed, Tylenol has one of the most favorable safety profiles among over-the-counter pain relievers," the McNeil statement said.
"We are aware of the recent JAMA Pediatrics study; however, there are no prospective, randomized controlled studies demonstrating a causal link between acetaminophen use during pregnancy and adverse effects on child development," the statement said.
The UCLA researchers based their findings on the Danish National Birth Cohort, a nationwide study of pregnancies and children. The study's aim is to examine pregnancy complications and diseases in children, with a specific focus on the side effects of medications and infections.
The researchers studied more than 64,000 children and mothers. They tracked acetaminophen use through telephone interviews conducted up to three times during pregnancy and then six months after childbirth.
The researchers then used Danish medical databases to see which children had been diagnosed with ADHD or were prescribed ADHD medications. They also used survey reports from parents to track whether the children had exhibited ADHD-like symptoms.
The results showed that children whose mothers took acetaminophen had a 37 percent higher risk of receiving a hospital diagnosis of hyperkinetic disorder, a particularly severe form of ADHD, the researchers found.
Those kids also were 29 percent more likely to use ADHD medication and 13 percent more likely to exhibit ADHD-like symptoms.
In addition, the risk for hyperkinetic disorder/ADHD in a child was elevated at least 50 percent when the mother used acetaminophen for more than 20 weeks during her pregnancy.
In their analysis, the researchers took into account the possibility that children's ADHD had been caused by maternal diseases that prompted the use of acetaminophen. "We adjusted for these, and it did not wipe out the acetaminophen effect at all," Ritz said.
Based on these findings, Ritz said she would caution pregnant women against using acetaminophen.