During the first month of pregnancy when a pregnant woman is in the early stages of pregnancy, a common cause of nipple pain is a change in hormone levels that causes the development of the mammary glands. After pregnancy, the estrogen, progesterone and HCG in a woman’s body will increase significantly. 48 hours after the fertilized egg is laid, the HCG value will double, while progesterone and estrogen will rise slowly and steadily, causing the development of breast follicles, hyperplasia of breast lobules, enlargement of breast ducts, and enlargement of nipples and areolas, which will result in breast pain and nipple swelling. Many pregnant women will also experience darkening of the nipples and obvious blood vessels in the breasts, which are all manifestations of breast development. At this time, pregnant women do not need to worry too much, to relax and maintain a calm state of mind, can take massage, cold compresses to relieve the pain. At the same time, eat more fresh vegetables and fruits, ensure sufficient sleep, do not stay up late, improve the endocrine status, and regular maternity checkups. However, if a pregnant woman has severe nipple pain, or can touch hard nodes, accompanied by changes in the skin of the breast, it may indicate a breast disease, it is recommended to go to the hospital to check the mammogram, to clarify the cause and then treat the cause.