Newborns often develop yellow skin 2-3 days after birth, mostly on the face and neck, and in severe cases the sclera, trunk, and limb skin is also yellow. Children generally have no other discomfort, and their spirits, milk intake and urination and defecation are normal. In preterm infants, jaundice is slightly more severe than in full-term infants, and jaundice can be delayed for 2 to 4 weeks. This is what is known medically as physiological jaundice. No special treatment is needed. However, if the jaundice in newborns appears too early, too deep, late or recede but reappears, this should be highly noted and the presence of infantile hepatitis syndrome should be determined.