Risk of trisomy 21
(Snijders et al. Ultrasound Obstet Gynecol 1999;13:167-70)
Maternal age (years)
Gestational age
10 weeks
12 weeks
14 weeks
16 weeks
20 weeks
40 weeks
20
25
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
1/983
1/870
1/576
1/500
1/424
1/352
1/287
1/229
1/180
1/140
1/108
1/82
1/62
1/47
1/35
1/26
1/20
1/15
1/1068
1/946
1/626
1/543
1/461
1/383
1/312
1/249
1/196
1/152
1/117
1/89
1/68
1/51
1/38
1/29
1/21
1/16
1/1140
1/1009
1/668
1/580
1/492
1/409
1/333
1/266
1/209
1/163
1/125
1/95
1/72
1/54
1/41
1/30
1/23
1/17
1/1200
1/1062
1/703
1/610
1/518
1/430
1/350
1/280
1/220
1/171
1/131
1/100
1/76
1/57
1/43
1/32
1/24
1/18
1/1295
1/1147
1/759
1/658
1/559
1/464
1/378
1/302
1/238
1/185
1/142
1/108
1/82
1/62
1/46
1/35
1/26
1/19
1/1527
1/1352
1/895
1/776
1/659
1/547
1/446
1/356
1/280
1/218
1/167
1/128
1/97
1/73
1/55
1/41
1/30
1/23

Pour GYNEWEB mise en page par le Dr J-M BRIDERON le 23/04/02