Three days after birth belongs to the newborn, when the jaundice index of the newborn reaches 17.1mg/dl, it means that the value is already higher than the normal physiological level. Within 24 hours after birth, the value of serum bilirubin may rise due to various factors, which is divided into two major types: physiological jaundice and pathological jaundice according to the difference in the value of the rise as well as the difference in clinical manifestations. 1. Physiological jaundice: although the jaundice index of newborns will gradually increase, the jaundice index of full-term newborns should be less than 12mg/dl, and that of preterm babies should not be more than 15mg/dl, and the jaundice index can be gradually restored to normal within a week or so, and the babies will not have any other abnormalities other than jaundice. 2. Pathological jaundice: when the jaundice index of full-term newborns reaches 12.9mg/dl or that of preterm newborns reaches 15mg/dl, it should be considered as pathological jaundice. In this case, in addition to jaundice, the newborn may also have abnormal body temperature, choking, vomiting, and stool color changes. When the jaundice index of the newborn exceeds the normal, it is important to consult the doctor in time and carry out standardized management under the guidance of the doctor.