Many pregnant women and new moms are told that taking over-the-counter painkillers is safe while pregnant and nursing, but new research suggests that even limited amounts of painkillers taken during pregnancy and infancy can lead to an increased risk of asthma for the unborn child.
The most recent study, conducted by a team of Norwegian researchers, used health data from 95,200 pregnant mothers between 1999 and 2008, and followed over 50,000 children after birth. After controlling for health and behavioral factors, the researchers found a 13 percent increase in risk for developing asthma by age 3 if the mother had taken Tylenol during pregnancy.
Previous studies that have shown a correlation between Tylenol use in infants and an increased risk in asthma were unable to rule out that the asthma was caused by the infection that Tylenol was taken for, not the drug itself. This study was designed to minimize that probability, and the link between Tylenol use during pregnancy and an increased risk for developing asthma in young children held true regardless of what condition the mother took the medicine for, such as pain, fever, flu or respiratory infections.
Before you panic, though, it's worth pointing out that the lead author of the study, Maria C. Magnus, of the Norwegian Institute of Public Health, told the New York Times that "based on this modest increased risk, there is no need to be concerned if a child has been exposed. It might be possible to limit the amount of Tylenol used, but mothers should not be afraid to use it when necessary."
Of course, this isn't the first time that Tylenol has been linked to childhood illness. Research has established links to ADHD in children whose mothers took Tylenol while pregnant, and a study released last year concluded that young boys who were exposed to the painkillers for extended periods of time had a sharp reduction in testosterone, which is critical for their development.