Peter Attia· MD
So, they then just divided the participants into three groups or tertiles based on the concentration of acetaminophen that was detected in the samples of umbilical cord blood. So then you could compare the risk in the first to the second and the first to the third tertiles respectively. So again this might eliminate the issue of recall bias um which of course is a real issue as well where you have to ask a woman after she has the baby you know how much Tylenol did you take during your pregnancy when etc. Um, but again it still has a pretty big issue which is acetaminophen does not stick around very long in the blood. Um, and therefore we don't really know how much the acetaminophen levels identified in cord blood at the time of delivery really tell us anything about the amount of acetaminophen that the woman took during pregnancy.