Risk For Any Chromosome Abnormality

Risk For Down Syndrome

Age

Risk

Percent

Risk

Percent

20

1 in 526

0.19%

1 in 1231

0.08%

25

1 in 476

0.21%

1 in 887

0.11%

30

1 in 385

0.26%

1 in 685

0.15%

31

1 in 346

0.29%

1 in 650

0.15%

32

1 in 310

0.32%

1 in 563

0.18%

33

1 in 274

0.37%

1 in 452

0.22%

34

1 in 238

0.42%

1 in 352

0.28%

35

1 in 100

1.00%

1 in 274

0.36%

36

1 in 90

1.11%

1 in 213

0.47%

37

1 in 80

1.25%

1 in 166

0.60%

38

1 in 70

1.43%

1 in 129

0.78%

39

1 in 60

1.67%

1 in 100

1.00%

40

1 in 50

2.00%

1 in 78

1.28%

41

1 in 40

2.50%

1 in 61

1.64%

42

1 in 30

3.33%

1 in 47

2.13%

43

1 in 25

4.00%

1 in 37

2.70%

44

1 in 20

5.00%

1 in 29

3.45%

45

1 in 18

5.56%

1 in 22

4.55%

46

1 in 16

6.25%

1 in 17

5.88%

47

1 in 13

7.69%

1 in 13

7.69%

48

1 in 10

10.00%

1 in 10

10.00%

49

1 in 7

14.29%

1 in 8

12.50%