Results All cases were success once time,among which 51 cases to be successful in the first time,and 1 case has less number of colone,we go on with culture and have good result.

• 结果52例羊水全部培养成功。其中51例一次培养即获得足够染色体分裂相,1例由于细胞克隆数少而依靠传代培养后获得成功。