Childbirth After 30: Breast Cancer Risk & Genetic Considerations

Question
I've heard that if a woman has her first child after age 30 she increases her chance of getting breast cancer. Is there some way to reduce this risk if a woman really does not want to have kids before age 30?

Answer
There is no increased risk of breast cancer by having a first baby after the age of thirty. There is a higher risk of chromosomal abnormalities in the baby after the age of 30. At the age of 30, the risk of Down's syndrome is 1 in 2700 pregnanies. At the age of 35 it is 1 in 350, and at the age of 40 it is 1 in 100.  However, breast disease is not effected by the age you have your first baby.