June 18th 2021Approximately 270,000 women are diagnosed with breast cancer each year in the United States alone. While there is consensus among national organizations including the US Preventive Services Task Force, the American Cancer Society, and the American College of Radiology that routine mammography screening should be performed in women 50 years and older, there is debate about the benefit-to-harm ratio of routine screening in average-risk women aged between 40 and 49 years. In this review, we examine risks and benefits of routine breast cancer screening starting at age 40 at the individual level, followed by evaluation of the role of advanced imaging techniques in screening women on a population level.