Acetaminophen is one of the most commonly used pain medications, and it is considered safe in pregnancy. However, experiments done on animals have shown its use may negatively affect neurodevelopment and cognitive function in offspring. It can also disrupt brain derived neurotropic factor (BDNF). Human research has shown an increased risk of movement disorders and ADHD-type behaviour in children whose mothers took the drug while pregnant. A study published in 2016 in the journal JAMA Pediatrics looked at 7796 mothers and their use of acetaminophen while pregnant. The findings revealed that indeed acetaminophen use may increase the risk of multiple behavioural difficulties in their children. Taking the drug in the second and third trimesters of pregnancy was significantly associated with increased risk of conduct problems and hyperactivity symptoms in children. The risks were highest when acetaminophen was taken in the third trimester. Those children experienced more emotional symptoms and higher total behavioural difficulty. Acetaminophen is one of the safest drugs we have, when used according to directions. It is important to remember that every drug has the potential to cause harm, particularly when used during pregnancy. Reference: Stergiakouli E, Thapar A, Davey Smith G. Association of acetaminophen use during pregnancy with behavioral problems in childhood: evidence against confounding. JAMA Pediatr 2016;doi:10.1001/jamapediatrics.2016.1775