The birth weight of a newborn baby is between 2.5 and 4 kg. A newborn baby with a gestational age of less than 37 weeks is called a preterm baby, one with a weight of less than 2.5 kg is called a low birth weight baby, and one with a weight of more than 4 kg is called a giant baby. Newborns have some special physiological characteristics, and the child’s resistance is also relatively weak, so we should pay attention to reasonable care and keep the room at the right temperature and humidity. If the jaundice is physiological, it does not require special treatment and will subside on its own within two weeks. If the jaundice is pathological, timely intervention is needed, as pathological jaundice has the risk of causing bilirubin encephalopathy.