The adult female breast has approximately 15-20 ducts. There are countless tiny ducts, and the ducts will be centered on the nipple and spread radially across the breast, converging at the areola. In adult women, each duct is connected to a lobule, and the lobules and ducts are arranged in a radial pattern toward the nipple, with the ducts opening at the nipple, and the milk produced by the lobules is transported outward in layers through the terminal ducts, and finally secreted through the nipple by the primary ducts. The number of breast ducts varies from person to person, but as long as there are 3-5 ducts open during breastfeeding, breastfeeding will not be affected. Breast ducts are the preferred site for intraductal papillomas, which have a certain tendency to become malignant and should be detected early and surgically removed early.