The purpose of breast massage is to encourage lymphatic drainage from the lymph vessels in and around the breasts. Promoting drainage may help prevent breast cancer and can also help relieve breast pain from a number of different causes, including pregnancy, breastfeeding, and PMS.
Some types of massage techniques can also help prevent or reduce scar tissue and adhesions around the breasts.
The fatty tissue of the breasts contains blood vessels, glands, milk ducts, ligaments, lymphatic vessels, and nerves. Lymphatic fluid from the breasts move through the lymphatic vessels into a system of glands (lymph nodes) that filter the fluid, removing toxins and other unwanted waste products.
These lymph nodes are linked with other lymph nodes throughout your body and are an important line of defense against the spread of disease. When lymphatic vessels and nodes work less effectively, often due to lack of physical movement or tight clothing (especially a badly fitted bra), your body’s immune system works less well, weakening the body's ability to resist disease.
Most massage therapists don't massage the breasts, and in some locations aren't legally allowed to do so. A massage therapist who does offer the massage should have specialized training, always ask your permission, and only do as much as you are comfortable with. Touching the nipples is not necessary.
Reasons NOT to massage your breasts include infection or an undiagnosed lump.
Self massage is often the best option for women. The following video shows one way to do self massage. Always be gentle to avoid damaging the ligaments that support the breasts.
Massage therapists who want to massage the breasts need good training and clear and appropriate boundaries. Here's more information for professionals.