Karen, Our hospital just started doing PKU testing at 24 hours, seemingly regardless of protein intake. Amazing how the test becomes accurate as the discharge time goes down. Eventually they will discover that they can do it on the cord blood and it will be accurate. When I first came to Illinois, (13 yrs ago), it had to be done at 72 hours and the rule was "9 ounces of protein intake, minimal. All babies weighed before & after bf, and if they hadn't had enough at 72 hours, were given formula to make up the difference. I don't know if this was a PHD dictum or one by the hospital. Then the discharge went to 48 hours, and within several years (it takes awhile), lo and behold, the PKU was suddenly accurate at 48 hours. Now that the discharge is 24 hours, the PKU test has followed suit. Perhaps they have changed HOW they test and it has become more accurate. I do wish they would discover how to do it with cord blood so they don't have to poke the babies. All babies in our hospital have the PKU done at 24 hours -- even babies in the NICU on IVs. Maybe write to the Illinois dept of public health in Springfield to get their protocol? Jan B.