Question

What are the odds of a young healthy couple (say...mid twenties) having a child with down syndrome?

Answer 1

Although no one knows for sure why DS occurs and there's no way to prevent the chromosomal error that causes it, scientists do know that as women get older they have a significantly higher risk of having a child with the condition. Down syndrome affects about 1 in every 800 babies born, with a lower risk in younger women and a higher risk in older women. At age 30, for example, a woman has less than a 1 in 1,000 chance of conceiving a child with DS. Those odds increase to 1 in 400 by age 35. By 42, it jumps to about 1 in 60.

Risk table from: From Hook EB. JAMA 249: 2034-2038, 1983

http://www.babymed.com/tools/down-syndrome-risk-calculator

Answer 2

http://www.wolfson.qmul.ac.uk/epm/screening/calcrisk.html

Further reading

Answer 3

Women at 35, 1 in 350; 1 in 100 by age 40; 1 in 30 by age 45.

Answer 4

Thanks for the medalS!!!

Answer 5

Awesome thank you!