Biliary atresia is a birth defect in which the bile ducts do not have normal openings, preventing bile from leaving the liver. 胆道闭锁是一种不正常发育，使得胆管不能正常打开，导致胆汁不能离开肝脏产生作用。
That is to say, before birth, certain hormones are deficient or their activity is impaired, and thus the typical development of the fetus toward maleness remains incomplete. 就是说，在个体出生之前，某种激素缺乏或激素活性降低，因此胎儿向男性方向正常发育未完成。
美
