The liver is the most immature of the gastrointestinal organs. The activity of the enzyme glucuronyl transferase is reduced, affecting the conjugation of bilirubin with glucuronic acid, which contributes to physiologic jaundice of the newborn. The liver is also deficient in forming plasma proteins, which likely plays a role in the edema usually seen at birth. Prothrombin and other coagulation factors are also low. The liver stores less glycogen at birth than later in life. Consequently, the newborn is prone to hypoglycemia, which may be prevented by early and effective feeding, especially breast-feeding.