A breast self-examination (BSE) is a technique that a woman can use to check her breasts and underarms using varying degrees of pressure to monitor for any possible changes that might indicate breast cancer. Along with clinical breast examinations (CBEs) and mammograms, BSEs are part of the main screening tools for breast cancer.

The purpose of a monthly breast self-examination is for a woman to gain familiarity with her breasts so that any changes in texture, including the presence of a lump, can be detected as early as possible. The American Cancer Society (ACS) recommends that women be educated on the benefits and limitations of performing a monthly BSE. Beginning in their 20s, women should consider performing BSEs as part of their breast health routine.

However, the ACS considers these examinations optional, rather than mandatory. If a woman chooses to perform monthly BSEs, they should be supported by clinical breast examinations (CBEs) performed by a physician every three years until age 40. At 40, women should have CBEs and screening mammograms every year.

The goal of BSEs is to detect breast cancers when they are at their earliest stages. Once breast cancers are large enough to cause symptoms, they are often more advanced than those detected during routine screening. Breast cancers caught during screening are usually smaller and less likely to have spread. For this reason, many health experts recommend monthly breast self-examinations as part of the screening process for breast cancer.

For those who are at in increased risk of developing breast cancer, such as having a mother, sister or daughter diagnosed with the disease, additional screening options should be discussed with a physician.