Before-period breast lumps: what to know

Hormonal shifts before menstruation can make breast tissue swell, feel tender, or seem nodular. Changes may affect both breasts and may ease after the period begins. A lump can also come from a cyst, a fibroadenoma, or another benign breast change. The timing alone cannot identify the cause, and a breast lump is a common presentation of breast cancer, so persistent findings need medical review without assuming the diagnosis.

Notice where the lump is, whether it moves, and whether it changes with your cycle. Recheck the area after your period, using gentle pressure rather than repeated squeezing. Wear a supportive bra if movement worsens tenderness, and use a simple pain reliever only if it is suitable for you. Arrange an appointment if the lump remains, returns in the same spot, or worries you. A clinician may examine the breast and decide whether imaging is useful.

Seek prompt medical assessment for a hard or fixed lump, skin dimpling, a newly inverted nipple, bloody nipple discharge, or a change in breast shape. Contact a clinician urgently if the breast becomes red, hot, very painful, or you feel unwell. Do not wait for the next cycle when a lump is rapidly changing or accompanied by concerning skin or nipple changes.

Ask whether the lump feels cyclical, what examination or imaging is appropriate, and which changes should prompt an earlier review. Tell the clinician when you first noticed it, whether it has changed since your last period, and whether breast cancer has affected close relatives.