Breasts have cracks normally refers to the nipple has cracks, may be the normal structure of the nipple itself, is a normal phenomenon, but also may be breastfeeding feeding posture is not appropriate or breast cancer and other reasons. 1. Normal phenomenon: cracks are the normal structure of the nipple itself, and the normal nipple is shaped like a mulberry. The surface has a road, there are raised, there are concave. Inside the nipple, in addition to the milk ducts, there are fibrous strips of tissue, ligaments and so on, which may appear cracked by pulling. 2. Improper feeding position: If you are breastfeeding and have a nipple crack, the nipple may be inverted or too small, and the baby is sucking too hard, resulting in nipple damage. 3. Breast Cancer: Breast cancer patients will have swollen and painful nipples, inverted and cracked nipples, nipple overflow, and need to be highly alert if accompanied by orange peel-like changes in the skin. When patients have symptoms of nipple cracks, accompanied by swelling and pain and other uncomfortable symptoms, they should go to the hospital in time to avoid delaying the condition and causing adverse consequences.