Physiological jaundice Characteristics: 1, full-term infants 2-3 days after birth jaundice, 4-5 days to reach the peak, 5-7 days to subside, but no later than 2 weeks; 2, premature infants jaundice more than 3-5 days after birth, 5-7 days to reach the peak, 7-9 days to subside, the latest delayed 3-4 weeks; 3, jaundice has a certain limit, its color will not be golden yellow; 4, jaundice is mainly distributed in the face and trunk, and Calves, forearms, hands and feet often do not have obvious jaundice; 5, the baby’s body temperature is normal, appetite is good, weight gain, stool and urine color is normal. Pathological jaundice Characteristics: 1, jaundice appears too early: full-term infants within 24 hours after birth, premature infants within 48 hours of jaundice; 2, jaundice degree is heavy: serum bilirubin exceeds the average value of normal children of the same age, or the daily rise of more than 85.5μmol/L (5mg/dl); 3, jaundice lasts a long time: full-term infants > 2 weeks, premature infants > 4 weeks, or after the jaundice subsides again appears; 4, jaundice progresses quickly, i.e., it deepens a lot in one day.