No nipple breasts are mainly caused by the occurrence of nipple invagination leading to invisible nipples, the main causes may be several: 1, congenital development, congenital dysplasia may lead to nipple invagination, as benign lesions, no need to worry. 2, obesity, some people are too obese, breasts are very large may also cause nipple invagination, need to pay attention to the cleanliness of the areola invagination to avoid infection. 3, mastitis, if the breast secretions block the ducts or ducts, may cause inflammation of the breast, resulting in pain and swelling of the breast. The treatment can be cefaclor capsules for anti-inflammatory and Siwip for pain relief, and hot towel compresses, supplemented by massage to relieve the symptoms. 4, breast cancer, breast cancer may also cause nipple invagination, we need to pay attention to whether there are cellulite-like changes in the skin, we suggest to see the hospital to improve the examination to clarify the cause.