In a disturbing study published in JAMA Pediatrics (2014;168(4):313-320), researchers at the University of Aarhus in Denmark found a strong correlation between acetaminophen (found in common pain killers like Tylenol) use among pregnant women and the rate of ADHD in their children. Overall, moms who used the pain reliever to treat headaches or to reduce fevers saw a 37 percent increased risk in their children receiving an ADHD diagnosis and a 29 percent increased risk in the chances their children received ADHD medications compared with moms who didn’t use the medication at all. Even after the team accounted for other factors, the link remained strong. The findings are especially troubling since more than sixty-four thousand women in the study reported using acetaminophen in the three months prior to the survey. Higher acetaminophen use among others was linked to higher rates of ADHD in their children. Scientists speculate that hormone disruptions in utero, triggered by acetaminophen, may cause enough imbalance in the brain to make certain children more vulnerable to autism or hyperactivity later in life.