当前90%以上产前诊断性检查是以孕妇高龄为指征。应向35岁或35岁以上的孕妇说明,她们生育具有染色体异常子女的危险性增加了,也要告诉她们产前诊断的可行性。现在往往是因为已知胎儿父母是遗传性疾病因子携带者;生育过有遗传性疾病的孩子;或有阳性家族史,才进行有关遗传性生化失调,神经管缺陷或其它先天性畸形等方面的产前检查。应该强调,在作出生化失 At present, more than 90% of prenatal diagnostic tests are based on gestational age as an indication. Pregnant women 35 years or older should be advised that they are at increased risk of having children with chromosomal abnormalities and that they are also advised of the feasibility of prenatal diagnosis. It is often because of the fact that fetal parents are known carriers of hereditary disease factors; children who have had a genetic disease; or have a positive family history are those who are involved in genetic biochemical disorders, neural tube defects or other forms of congenital malformations Prenatal care. It should be emphasized that in making biochemical loss