Young I D, Williams E M, Newcombe R G
J Med Genet. 1980 Dec;17(6):433-6. doi: 10.1136/jmg.17.6.433.
Seventy cases of Down syndrome have been ascertained in South Glamorgan during the period 1968 to 1976. This gives an overall incidence of 1 in 658 live births. Analysis of the data on the basis of single years of maternal age gives an incidence of 1 in 200 by 36 years, 1 in 100 by 40 years, and 1 in 50 by 44 years. All incidence figures are for live births at age of delivery.
1968年至1976年期间,南格拉摩根郡确诊了70例唐氏综合征病例。这使得活产儿的总体发病率为1/658。按母亲年龄单年对数据进行分析,36岁时发病率为1/200,40岁时为1/100,44岁时为1/50。所有发病率数据均针对分娩时的活产儿。