I'm breastfeeding a four-month-old and am worried about a lump in my breast. Could it be a milk duct, even if it doesn't feel clogged? Can the breast be properly examined without weaning? If my doctor recommends a mammogram, will that require weaning?

--M.

Most likely, what you are feeling is a benign lump due to a blocked milk duct or just the normal enlargement of the milk-producing glandular tissue of the breasts. This does not mean, however, that lumps should be ignored in nursing women -- see your doctor for a breast exam. Depending on the size, location and consistency of the lump, your doctor may recommend close follow-up, aspiration, mammogram or ultrasound, or biopsy.

Mammograms can be done in nursing women, although they may be more difficult to interpret due to the density of the breasts. Ultrasounds to evaluate whether a lump is cystic (fluid-filled) or solid can provide additional valuable information. If your doctor does recommend a mammogram, you will not need to wean your baby first.