There are two reasons why babies urinate less at night, and specific problems need to be analyzed, the reasons are as follows: First, abnormal kidney function: If the kidney function is abnormal, it will lead to less urine, and this time parents should take their babies to the urology department of the hospital for a detailed examination to make a clear diagnosis and timely treatment. Second, normal physiological phenomenon: if the baby’s urine volume during the day is normal, and only the night urine is low, it is likely to be a normal physiological phenomenon, because the baby before going to bed, or at night into the water is relatively small, so it will lead to less urine, which is a normal physiological phenomenon.