"Acetaminophen in both OTC (ie Tylenol) and prescription products and the risk of attention deficit hyperactivity disorder (ADHD) in children born to women who took this medicine at any time during pregnancy." Circa 2015. Seems paediatricians just ignored this warning and declared this safe and effective.

U.S. Food and Drug Administration

FDA Drug Safety Communication: FDA has reviewed possible risks of pain medicine use during pregnancy | FDA