If you are in the developmental period of puberty, the breast tissue begins to develop normally the breast gland increases significantly, the nipple and areola increase in size, and the color of the areola darkens, which is a normal physiological phenomenon. This is due to the increased pigmentation of the areola due to the influence of estrogen levels, and the color deepens. In addition, women who become pregnant are also affected by increased levels of estrogen and progesterone in the body, which increases the pigmentation of the areola, resulting in a darker areola. This is a normal physiological phenomenon to prepare for breastfeeding and is not a cause for concern. In rare cases, the areola can be stimulated by excessive friction, such as often wearing rough underwear, causing skin lesions can also appear areola color deepening, you can go to the hospital to let the doctor check the diagnosis of the specific situation.