What causes neonatal jaundice?

Neonatal jaundice, medically termed neonatal hyperbilirubinemia, refers to the yellowing of the skin, mucous membranes, and whites of the eyes caused by elevated bilirubin levels in the blood due to abnormal bilirubin metabolism during the neonatal period. Jaundice appearing in the neonatal period may have multiple causes: 1. Physiological jaundice: During fetal development, the infant is in a relatively hypoxic state. After birth, with the establishment of pulmonary respiration and increased oxygen tension, a large number of red blood cells are destroyed. The liver cannot process the resulting bilirubin efficiently, leading to physiological jaundice, which typically lasts about two weeks. 2. Blood group incompatibility, such as ABO or Rh hemolytic disease: Hemolytic jaundice can occur in infants within 24 to 48 hours after birth. 3. Delayed breastfeeding: Certain components in breast milk may inhibit the liver enzymes responsible for bilirubin processing, causing prolonged jaundice. Clinically, this often manifests as persistent jaundice after the resolution of physiological jaundice. 4. Biliary atresia: Structural abnormalities prevent the excretion of directly processed bilirubin from the liver into bile, leading to the development of jaundice clinically.