妊娠16周时进行羊水细胞核型分析的指征有如下四种:母令≥38者;可能再次娩出Down’s综合征者;双亲中的一方是染色体结构异常或性连锁疾病的携带者;曾出生过染色体异常及神经管缺陷的子女者。所有的样品均进行染色体研究及甲胎球蛋白测定。研究的对象约三分之一因年令过大,而神经管缺陷和有再次发生Down’s综合征危险者占第二位和第三位。对32例双亲一方具有染色体结构异常的妊娠进行了研究,发现有七例胎儿核型是异常的。经超声检查没立即进行羊水穿刺,可减少穿刺失败及血液污 There are four indications for karyotype analysis of amniotic fluid cells at 16 weeks of gestation: maternal orders ≥38; Down’s syndrome may be delivered again; one of the parents is a chromosomal structural abnormality or a carrier of sex-linked disease; Chromosomal abnormalities and neural tube defects in children. All samples were subjected to chromosomal and alpha fetoprotein assays. Approximately one-third of the subjects studied were over-age, with neurological deficits and those at risk of recurrent Down’s syndrome taking up second and third place. Thirty-two pregnancies with chromosomal abnormalities in one of the parents were studied and found that seven of the fetuses had an abnormal karyotype. The ultrasound did not immediately amniocentesis, can reduce the puncture failure and blood pollution