The photo below shows a lateral view of the breast with the underlying anatomical structures superimposed. The lactiferous sinuses are located under the areola of the breast. The lactiferous sinuses drain out through the nipple. Lactiferous sinuses may open into Montgomery's tubercles or adjacent to them.
Milk is produced in the alveolus .
The alveolus is made up of gland cells around a central duct. The milk is produced by the gland cells. Surrounding the gland cells are the myoepithelial cells which contract to cause milk ejection into the milk duct. The milk then travels down into the lactiferous ducts and into the lactiferous sinuses. A cross-section view of the alveolus.