Crane Elizabeth, Morris Joan K
Centre for Environmental and Preventive Medicine, Wolfson Institute of Preventive Medicine, Barts and The London, Queen Mary's School of Medicine and Dentistry, Charterhouse Square, London ECIM 6BQ, UK.
Downs Syndr Res Pract. 2006 Jul;10(1):41-3. doi: 10.3104/reports.304.
The risk of having a pregnancy with Down syndrome increases with maternal age. The percentage of all births in England and Wales to mothers aged 35 and over increased from 9% in 1989 to 19% in 2003. A 51% increase in the numbers of pregnancies with Down syndrome has been observed over the same time period (from 954 to 1440). Due to improvements in antenatal screening for Down syndrome and the subsequent termination of affected pregnancies, the total number of births with Down syndrome decreased from 770 in 1989 to 609 in 2003. However the number of births with Down syndrome to women aged 35 and over increased from 186 in 1989 to 310 in 2003 because of the increasing number of pregnancies amongst these women.
怀有唐氏综合征胎儿的风险会随着母亲年龄的增长而增加。在英格兰和威尔士，35岁及以上母亲所生育的婴儿在所有出生婴儿中的占比从1989年的9%上升至2003年的19%。在同一时期，怀有唐氏综合征胎儿的妊娠数量增长了51%（从954例增至1440例）。由于唐氏综合征产前筛查的改善以及对受影响妊娠的后续终止，唐氏综合征患儿的出生总数从1989年的770例降至2003年的609例。然而，由于35岁及以上女性怀孕数量的增加，该年龄段女性所生育的唐氏综合征患儿数量从1989年的186例增至2003年的310例。
