Congenital liver defects are liver disorders that are present at birth. They are rare. These liver disorders usually block the bile ducts. This affects the flow of bile. Bile is a fluid made in the liver. It helps with digestion. The bile ducts take bile from the liver and bring it to the gallbladder to be stored. Then they carry bile to the small intestine for digestion.

When the bile ducts are blocked, bile builds up in the liver. This damages the liver.

Some congenital liver defects include:
Biliary atresia. A life-threatening condition in infants where the bile ducts are blocked or have developed abnormally. This blocks the flow of bile from the liver.
Biliary (choledochal) cyst. A condition where the hepatic duct forms abnormally. This can also block the flow of bile.
Alagille syndrome. Too few bile ducts associated with other abnormalities including heart, bone, facial features, eye, and others.