What happened to the nipples becoming larger and darker? The nipples become bigger and darker in several cases: first, pre-pubescent women when their breasts begin to develop, the nipples begin to grow larger from childhood, about a dozen years old, of course, with the beginning of the menstrual cycle nipples also begin to gradually become larger and darker, the breasts also begin to develop, this is the first case, is normal. Secondly, the nipples become bigger and darker during pregnancy, once the eggs are fertilized and the fertilized eggs are planted in the endometrium, the nipples and breasts, including the areola, change and the breasts start to get bigger and fuller, ready to secrete milk to feed the newborn, and of course the nipples and areola start to get bigger and darker, which is also a normal physiological manifestation. Third, the nipple may become larger and darker unilaterally. If the nipple becomes larger and darker unilaterally, and it is not during pregnancy or puberty, there may be some problems, so you need to go to the dermatology department or to the mammary department for some related examinations to see if there is a problem with melanin on the nipple, if the melanin in the skin has increased, and if there are any dark pigmented nevi or melanomas.