What does it mean if my infant's urine smells really bad?

Possible infection. If your baby has a very strong odor to the urine, contact your pediatrician. This could be a sign of a urinary tract problem and might be serious. Watch for signs of fever, irritability, or pain. Keep the baby well hydrated.
Stinky pee=need2see. We all know poop can be stinky, but the pee should not be. The main concern is urinary tract infection (uti), which can lead to severe kidney infection if untreated. It is not easy to diagnose a UTI by sight or smell, so a properly obtained urine culture is important. Sometimes we find no infection, just a temporary bad smell, but this is one of those infections we would not want to miss!