I assume you mean from 35 to 40? The odds jump from 0.5% to 1% for Down Syndrome specifically; risk of any birth defect would be higher. That said, the bigger

I assume you mean from 35 to 40? The odds jump from 0.5% to 1% for Down Syndrome specifically; risk of any birth defect would be higher. That said, the bigger issue is infertility, which increases by 20%: http://en.wikipedia.org/wiki/Age_and_female_fertility http://en.wikipedia.org/wiki/Age_and_female_fertility