Aren't most children born with Down syndrome born to older parents?
This is false. Most children with Down syndrome are born to women younger than 35 years old simply because younger women have more children. However, the chances of having a child with Down syndrome increases with the age of the mother, especially after age 35.
A woman's chances of giving birth to a child with Down syndrome increase with age because older eggs have a greater risk of improper chromosome division.
The chances of conceiving a child with Down syndrome:
- Under age 25 - 1 in 1,400
- By age 35 - 1 in 350
- By age 40 - 1 in 100
- By age 45 - 1 in 30
As the average age of women becoming pregnant increases, Down syndrome is being diagnosed more frequently.
What are other factors?
- A woman who has one child with Down syndrome has about a 1 in 100 chance of having another child with Down syndrome.
- Both men and women can pass the genetic translocation for Down syndrome on to their children.