应用扩增片段长度多态性（ａｍｐｌｉｆｉｅｄｆｒａｇｍｅｎｔｌｅｎｇｔｈｐｏｌｙｍｏｒｐｈｉｓｍ，Ａｍｐ－ＦＬＰ）分析法，对５０例高危孕妇进行孕中期羊水细胞检测，检出３例胎儿为唐氏综合征，实现了该病的超早期诊断。 A total of 50 pregnant women at high risk were tested for amniotic fluid cells during the second trimester of pregnancy by using amplified fragment length polymorphism (Amp-FLP) analysis. Three fetuses were diagnosed as Down’s syndrome and the ultra-early diagnosis of the disease was achieved.