染色体异常在新生儿的发病率约为0.1%~0.2%,其中唐氏综合征发病率最高。产前超声检查胎儿畸形伴染色体异常的价值已得到肯定,可以检查出包括21-三体、13-三体、18-三体、三倍体综合征和Turner综合征等染色体疾病。早孕或中孕期超声筛查出的2个及以上超声软指标异常,可更早提示胎儿染色体异常或结构畸形,这些软指标包括胎儿颈部皱褶、心室内强回声点、肠管强回声、脉络膜囊肿、轻度肾盂扩张、长骨短小等。本文将系统回顾常见的超声软指标,讨论其在染色体异常胎儿中风险评估价值、筛查技巧和测量标准,以期超声在产前诊断中获得更好的实用价值。 Chromosomal abnormalities in the incidence of neonatal rate of about 0.1% to 0.2%, of which the highest incidence of Down Syndrome. The value of prenatal ultrasound in detecting fetal abnormalities with chromosomal abnormalities has been affirmed, and chromosomal disorders including 21-trisomy, 13-trisomy, 18-trisomy, triploid syndrome and Turner syndrome can be detected. Two or more ultrasonic soft-mark abnormalities found in early or second trimester ultrasonography may be an early indication of fetal chromosomal abnormalities or structural deformities. These soft indices include fetal neck fold, ventricular echo points, strong bowel echoes, choroid Cyst, slight pyelonephrosis, long bones short and so on. This article will review the common system of ultrasound soft index, to discuss its risk assessment in fetal chromosomal abnormalities, screening techniques and measurement standards, in order to ultrasound in prenatal diagnosis to obtain better practical value.