Breast changes after pregnancy are mainly reflected in breast swelling and pain, enlargement and deepening of areola. After pregnancy, under the action of progesterone and estrogen in the body, mammary gland ducts proliferate, mammary gland follicles develop, breasts will be swollen and painful, and the breast volume will gradually appear to be enlarged. At the same time, the surface of the breast will show more obvious veins. The nipple will gradually increase in size with the breast and the areola will deepen in color. A special type of Montgomery’s nodule, a dark brown nodule with sebaceous glandular hyperplasia around the areola, is also present. Changes in the breasts occur gradually with pregnancy, and the essence of the change in volume is to create conditions for breastfeeding of the fetus. The mammary glands produce a large amount of milk at the end of pregnancy and will gradually decrease in milk after the breastfeeding period. Their volume and color may gradually return to their original state, but their areola, hyperpigmentation may not be completely restored.