Lactiferous duct

Lactiferous ducts are the structures in the female mammary gland that transport milk from where it is produced, to the nipple. They are also referred to as galactophores, galactophorous ducts, mammary ducts, milk ducts and mammary gland ducts.

Anatomy

The lactiferous ducts are not noticeable until a woman gets pregnant and the hormones prolactin and progesterone stimulate the growth of the ductal system within the breasts.

Each breast has between 4 and 18 lactiferous ducts that converge and open at the nipple. The ducts are lined with a layer of epithelial cells and are surrounded by smooth muscle.

Function

The primary function of the lactiferous ducts is to transport milk from the lobules, where it is produced, to the nipple. The milk is then available to a nursing infant. The ducts expand and store milk in response to the hormone oxytocin.

Clinical significance

Inflammation of the lactiferous ducts is known as mastitis. This can occur when a milk duct becomes blocked. Mastitis can cause the breast to become red, swollen and painful.

Ductal carcinoma in situ (DCIS) is a type of breast cancer that starts in the cells that line the lactiferous ducts. DCIS is considered non-invasive because it hasn’t spread beyond the milk duct into any normal surrounding breast tissue.

See also

• Mammary gland
• Breast cancer
• Mastitis

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  Breast anatomy normal scheme