The US Preventative Services Task force (USPSTF) is the major US body that makes recommendations related to what screening tests have a benefit. There has been a recent change in what they recommend for women aged 40 to 49 years. The recommendation is as follows:
The USPSTF recommends against routine screening mammography in women aged 40 to 49 years. The decision to start regular, biennial screening mammography before the age of 50 years should be an individual one and take patient context into account, including the patient’s values regarding specific benefits and harms.
What does this mean? Basically routine screening if you have no symptoms, no family history or risks is no longer recommended until the age of 50 years. If you decide to have a mammogram prior to this age you should discuss the pros and cons with your Doctor. Why the change? Breast cancer is not common under 50 and many benign changes are discovered on mammograms that necessitate further investigation. To avoid unnecessary investigation the balance is against have routine screening done.