What causes biliary atresia?

Biliary atresia has no known specific cause, but doctors do know that it is not an inherited disease. There is a list of triggers that are suspected of leading to the disease, which can occur while the child is still in the womb or up to a few weeks after birth. Viral or bacterial infections; a developmental problem in the liver; a bile problem and immune system issues are all suspects. Each can cause bile ducts to develop abnormally and eventually set off biliary atresia.