I always ask several questions. For some women any of these things can increase breast lumps. This is especially true if the lump shrinks and becomes less tender after the period begins. If the lump seems to be benign, I would then advise the woman to take a natural form of Vitamin E with selenium and grapeseed extract and GLA or borage seed oil capsules. She can also try rubbing the GLA or castor oil into the skin at the site of the lump two times each day.
Some women also find hot ginger compresses helpful.
If the lump does not go away after the menstrual period, or if it is hard, non-tender and not movable, see you health care practitioner as soon as possible. Although many of the lumps turn out not to be cancerous, lumps of any kind should be taken seriously. In the meantime, using self-care modalities such as the ones I have outlined won't hurt anything. If you are unsure about how to perform self breast examinations, contact your health care provider or you local American Cancer Society for a brochure. Doing monthly exams just after your period, or if you are no longer having periods, the first of every month, can be a loving way to ensure breast health.