There are numerous causes of nipple swelling, but these are the common ones. The first, nipple swelling due to breast enlargement, can be definitively diagnosed by a doctor’s palpation and an ultrasound of the breast. There is often no redness or swelling of the nipple, and there is no peeling, crusting or bleeding. The second type, because the underwear worn too tight pressure on the nipple caused by nipple swelling and pain, physical examination, that is, the doctor’s palpation and color ultrasound can be ruled out, the nipple is generally no redness and swelling, there is no lumps, and there will be no peeling of the skin phenomenon. The third kind, because the nipple localized inflammation inflammation, usually can find redness, swelling, pain. The fourth type, because the nipple inside the growth of intraductal papilloma combined with swelling and pain, gently touching the nipple with the hand will feel a small nodule. The fifth type of nipple swelling and pain during breastfeeding is due to inflammation, this is easier to identify, during breastfeeding because of the swelling and pain of the nipple, it is easy to find out by yourself. The sixth type, nipple swelling caused by breast cancer, is also easy to detect if it does progress to this point. Other chronic inflammation of the mammary glands invades the nipple and is easily detected by the doctor’s palpation. That’s why nipple swelling should still be checked by a specialist with palpation and ultrasound, with the addition of an MRI if necessary. But the most common ones are still dominated by breast enlargement and inappropriate wearing of underwear, often caused by too tight underwear.