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Determine the grade of your inverted nipples. Identify the cause. Decide on a treatment method.
Take off your shirt and stand in front of a mirror. Holding your breast at the edge of the areola (the dark area of skin surrounding the nipple) between your thumb and forefinger, press inwards about an inch behind your nipple. Be firm but gentle. Depending on the nipple's response, you can assess the grade of inversion.  Grade 1: The nipple protracts easily when you apply light pressure to the areola. When pressure is released, the nipple maintains its projection, rather than retracting immediately. Grade 1 inverted nipples are unlikely to interfere with breastfeeding, though you still may have cosmetic concerns. There is little to no fibrosis (excess connective tissue) in Grade 1 inverted nipples. Grade 2: The nipple protracts when pressure is applied, though not very easily, and retracts as soon as pressure is released. Grade 2 inversions are more likely to complicate breastfeeding. There is often a moderate degree of fibrosis, with mild retraction of the lactiferous or milk ducts. Grade 3: The nipple is retracted and does not respond to manipulation; it cannot be pulled out. This is the most serious form of inversion, with a significant amount of fibrosis and retracted milk ducts. You may also experience rashes or infections if you have Grade 3 inversion, and breastfeeding may be impossible.  Test both nipples, since they may not both be inverted. If you have had inverted nipples since childhood or puberty, your nipples are unlikely to be indicate an underlying problem. If they have changed recently, especially if you are over 50, they could indicate an illness or infection. Cancer and other serious conditions like inflammation or infection can occasionally cause inverted nipples.  If you are over 50 and your areola appears distorted and your nipple appears flatter than normal, or has become inverted, get screened for breast cancer immediately. Women over 50 are at risk for developing Paget's disease of the breast. Pink discharge and crusting, thickening, flaking, or scaling of the skin of the nipple and areola can also be symptoms of breast cancer. See a doctor if you have dirty white, greenish, or black discharge from your nipple. Tenderness, redness, or a thickening around your nipples may be a sign of mammary duct ecstasia. Perimenopausal women are especially at risk for mammary duct ecstasia. If you develop a painful lump that oozes pus when pushed or cut, and if you have fever, you may have a type of infection called subareolar breast abscess. Most nipple infections happen during lactation, but subareolar breast abscesses appear in women who are not lactating. If your nipples have been recently pierced and have become inverted, ask your doctor to check you for subareolar breast abscess. The treatment method depends on the grade of your inversion, the cause of your inversion, and whether you are planning to breastfeed. If you have signs of breast cancer, infection, or mammary duct ecstasia, visit your doctor immediately.  If you have Grade 1 inversion, it's likely that manual methods can help loosen the fibrous tissue and allow the nipple to protract more easily. If you have Grade 2 or 3 inversion, it may be a good idea to consult a doctor for your treatment plan. In some cases, non-invasive methods may be adequate, while plastic surgery may be a better option in others. If you are pregnant or nursing, be guided by your doctor, nurse or lactation consultant.