Scientists agree that Down syndrome can be attributed to the father in 5 to 10 percent of cases, and some believe that number may be as high as 20 percent.
Which parent causes Down syndrome?
To date, no behavioral activity of the parents or environmental factor is known to cause Down syndrome. After much research on these cell division errors, researchers know that: In the majority of cases, the extra copy of chromosome 21 comes from the mother in the egg.
Who is most likely to have a Down syndrome baby?
Women who are 35 years or older when they become pregnant are more likely to have a pregnancy affected by Down syndrome than women who become pregnant at a younger age. However, the majority of babies with Down syndrome are born to mothers less than 35 years old, because there are many more births among younger women.
Does mothers age increase Down syndrome?
Between 1979 and 2003, the number of babies born with Down syndrome increased by about 30%. Older mothers are more likely to have a baby affected by Down syndrome than younger mothers. In other words, the prevalence of Down syndrome increases as the mothers age increases.
Can a Down syndrome baby look normal?
Some of the children with Mosaic Down syndrome that we know do not actually look as if they have Down syndrome - the usual physical features are not obvious. This raises some important and difficult social issues and identity issues for both parents and children, which parents have discussed with us.