Mammary duct ectasia

Clogged milk duct in mammary duct ectasia

Mammary duct ectasia occurs when one or more milk ducts beneath the nipple becomes wider (dilated). The duct may also fill with fluid and become blocked or clogged with a thick, sticky substance. Mammary duct ectasia usually causes no signs or symptoms, but some women may have nipple discharge, breast tenderness or inflammation of the clogged duct.