Acetaminophen (Tylenol) during pregnancy may increase risk of hyperactivity in kids

(CNN)Women who take acetaminophen during pregnancy are more likely to have a hyperactive child, according to a new study. Prenatal exposure to the medication was associated with a higher risk of having children who exhibit emotional or behavioral symptoms, the researchers said.

Acetaminophen, also known as paracetamol, relieves pain and fever and is the active ingredient in Tylenol and hundreds of over-the-counter and prescription medicines, says the Food and Drug Administration website. More than half of all pregnant women in the United States and Europe use acetaminophen, which is also found in medicines for allergies, colds, flu and sleeplessness, according to the authors of the study published in JAMA Pediatrics.

"Acetaminophen is considered safe to use during pregnancy," said Evie Stergiakouli, lead author. She explained that, as with any medication used by mothers-to-be, it should be used only when necessary. A woman and her doctor need to carefully weigh the risks of not treating fever or pain against potential harm to the baby.