通过近十余年出生的１０３名先天愚型儿、４８１名健康儿以及５０－７０年代出生的２５９６名健康人出生时母亲年龄比较发现，虽然高龄（≥３５岁）妇女与先天愚型儿出生之间的联系依然存在，但因＂一个家庭，一个孩子＂政策的实施，高龄孕产妇占孕产妇总数的比例已明显下降，这既有助于降低先天愚型儿总的出生频率，又使依赖母龄的产前诊断先天愚型胎儿的难度加大。 A comparison of mothers’ age at birth by 103 naïve children, 481 healthy children born in the past 10 years and 2596 healthy people born in the 1950s and 1970s found that although women (older than 35 years) and children born with Down’s syndrome However, due to the implementation of the “one family and one child” policy, the proportion of older pregnant women to the total number of pregnant women has dropped significantly, which not only helps to reduce the total frequency of births among children of Down’s syndrome but also enables Premarital mother-dependent diagnosis of Down’s syndrome is more difficult.