The phenomenon of enlarged nipples occurs after pregnancy because the placenta secretes estrogen that stimulates the nipples and causes the nipples to become larger, the color of the nipples and areolas to deepen, and the areola to expand. Especially in the middle and late stages of pregnancy, the ducts are dilated, there is milk secretion, and the dilated veins can be seen on the surface of the breast, which are normal and do not require special treatment. Try to pay attention to hygiene and washing, and wear loose cotton underwear to reduce local skin irritation and facilitate blood circulation. If the underwear worn during pregnancy is too tight, it is not conducive to blood circulation and can lead to breast pain or swelling, which is not conducive to milk secretion and in severe cases can lead to inflammatory nipple infection and redness and swelling.