Five-month-old baby urine is not necessarily normal, need to be based on the 24-hour urine output and the presence of other adverse accompanying symptoms to decide, may be related to physiological factors, but also may be related to fever, diarrhea, urinary tract infections and other pathological factors. 1. Physiological factors: when the environment is hot and stuffy, the baby drinks less milk, clothing overdressed and so on leading to a lot of sweating, easy to dehydration, if there is no timely rehydration, the baby will urinate less, the need for timely supplemental water, reduce clothing. 2. Pathological factors: five-month-old baby body immune system is not yet well developed, prone to acute respiratory infections, urinary tract infections, etc., water loss due to fever sweating, stool, urinary tract infections when the baby’s urine volume and frequency will also be reduced, these cases of reduced urination is generally accompanied by fever, coughing, diarrhea, urination crying and other symptoms. Need to consult a doctor in time. So the baby’s urine volume is reduced for more reasons, when you find that the baby’s urine volume is reduced, by drinking more water, reduce clothing, etc. without improvement, or the baby accompanied by other symptoms of discomfort, please take the baby to the hospital in time to find out the cause of the disease.