Acetaminophen, the most common drug taken by pregnant women, may be linked to attention deficit hyperactivity disorder (ADHD) in children, according to a large but preliminary new study from Denmark.
The study, published Monday in JAMA Pediatrics, found the disorder was more likely to develop in children whose mothers took the medication while pregnant.
Experts say the study does not prove a cause-and-effect relationship and more study is needed. It is likely to prompt concerns among women who have been told that the medication – found in Tylenol and many other pain and fever remedies – is safe during pregnancy.
The study is a reminder that "anything we do in pregnancy we should not do lightly," says one study author, Beate Ritz, an epidemiologist at the University of California-Los Angeles. She worked with researchers from the University of Aarhus in Denmark and other institutions.
The researchers looked for a link between acetaminophen and ADHD because they believe the medication might work as a hormone disruptor capable of affecting fetal brain development, Ritz says.
The study included more than 64,000 Danish children born from 1996 to 2002. The mothers of those children were called twice during pregnancy and once six months after birth and asked about painkiller use.
