Fibrocystic breast disease, characterized by lumps in the breast, is caused by the changing of hormones during menstruation. These lumps are often palpable in both breasts, but do not usually have clear borders and may not be fully felt by hand. The skin on the breast may appear “wrinkled” or have dimples. The lumps are usually not hard and are moveable. Some women experience pain or discomfort, sometimes at the lumps themselves and sometimes under their arms. The breasts may feel hard or swollen. Symptoms usually worsen just before a menstrual period and improve during menstruation. Birth control pills can alleviate these symptoms while hormone replacement therapy, such as prescribed after ovarian surgery, may worsen the symptoms. These lumps do not usually become cancerous.