The most prevalent reason for a juvenile liver transplant is biliary atresia (BA). BA’s variable presentation, natural history, and treatment with the Kasai portoenterostomy have all been extensively reported; nevertheless, the timing of BA’s onset in relation to birth has not been completely established. Researchers examined the laboratory, imaging, and clinical findings that showed that most, if not all, types of BA began before birth. This early onset had ramifications for administering medicines sooner and discovering potential elements driving BA’s genesis.