User: Why do some babies need to stay in the NICU?
Assistant: Babies may need to be admitted to the NICU for a number of reasons after being born.  The primary reason is premature birth, which can cause a number of complications such as respiratory distress syndrome, hypoglycemia, apnea, low birth weight and bradycardia.  A baby will typically stay in the NICU until their complications are resolved and they are healthy enough to be discharged.