A breast self-examination (BSE) is a technique that women can use to check their breasts and underarms using varying degrees of pressure to monitor for any possible changes. The BSE is part of a three-step process, including clinical breast examinations (CBEs) and screening mammography, advocated by the American Cancer Society to screen for breast cancer.

BSE may be recommended for women starting in their 20s, even though the incidence of breast cancer in this age group is extremely low. In addition to annual screening mammograms and clinical breast examinations (CBEs) for women over 40, some experts also recommend performing a monthly breast self-examination.

Performing monthly BSEs was first advocated in the 1950s by Columbia University breast surgeon, Cushman Haagensen. At the time, mammography had yet to be developed and women were usually diagnosed when the breast tumor had become large and inoperable. Haagensen hoped that encouraging breast self-examinations would help catch tumors earlier when they were still treatable.

Since that time, several large studies have concluded BSE may not help find breast cancers at earlier stages and may in fact lead to a higher incidence of unnecessary surgical biopsies. For this reason, some health experts believe that as a method to detect breast cancer, BSE is ineffective. However, with long-term studies still being conducted, the debate is far from over.

For certain women who are at an increased risk of developing breast cancer, including a family history of the disease, the ACS recommends that:

• Screening  begin at an earlier age
• Time between screenings be reduced
• Include additional screening methods, such as an ultrasound or magnetic resonance image (MRI)

In addition, women at high risk are advised to begin annual mammograms and CBEs no later than 10 years before the age a first-degree relative (mother or sister) was diagnosed with breast cancer. For example, a woman whose mother was diagnosed at age 43 should begin additional screening by age 33. A woman should check with her physician to see if the additional screening includes monthly BSEs.

There is some disagreement as to when a woman should perform monthly breast self-examinations. They should not be performed when a woman’s breasts are swollen or tender. Many health care experts believe that there is an advantage to performing the BSE at the same time each month, usually five to seven days after menstruation. Other experts believe that there are distinct advantages to checking the breasts at different times of the month so that a woman becomes familiar with how her breasts feel at all times. Regardless of when women choose to conduct BSEs, they should have their examination technique reviewed by a knowledgeable healthcare professional. Conducting the exam regularly can help women learn the normal look and feel of their breasts.