The 40 to 50 year old window is so important for breast health. One in six breast cancers are diagnosed in this decade and those tend to be more aggressive. If you look at years of life extended that is where we can have the largest impact. We want our 40 year olds to live to their 90s and 100s. That's our goal. Every time you skip a year with a mammogram you give breast cancer a chance to grow. The doubling time for breast cancer is right at one year. You give cancer a leg up every time you skip a mammogram.