Best to start breast cancer screening at 40

Under the U.S. Preventive Services Task Force guidelines, mammogram screening every two years for women 50 to 74 got a grade of “B”, meaning doctors should offer the service. Screening for women in their 40s got a “C” grade, meaning doctors should offer the service for select patients, depending on individual circumstances. 

Debate over the proper age at which doctors should start offering screening mammograms has raged since the task force first issued its recommendation in 2009. At the time, the panel cited evidence showing that the harm from over screening outweighed the benefits in cancer prevention. 

Since that time, the task force has maintained that 50 is the best age to start routine screening. But it has left the door open for individuals who might benefit from screening starting at age 40. 

The new, more inclusive wording of the guidelines is more in line with new recommendations from other cancer groups, such as the American Cancer Society. The society released new breast cancer screening guidelines in October pushing back the starting age for screening mammograms to 45 from 40, and recommending that younger women should have the choice to start screening as early as 40.