Most Effective Breast Cancer Prevention Is Having Children Early

From "Here is why having a baby reduces breast cancer risk":

Many women fail to realize the single most effective measure they can take to reduce their risk of developing breast cancer is to have a baby as early as they can and avoid any induced abortion.
***Studies have shown having a full-term pregnancy or having a baby at age 18 can reduce the risk of breast cancer by 50 to 75 percent compared to those who have a baby at 30.

Read the complete article for an explanation of why carrying a pregnancy to term at a young age reduces breast cancer risk here.