The human areola ( areola mammae , / ə ˈ r iː ə l ə / or / ˌ ær i ˈ oʊ l ə / ) is the pigmented area on the breast around the nipple . More generally, an areola is a small circular area on the body with a different histology from the surrounding tissue , or other small circular areas such as an inflamed region of skin.
8-471: The mature human female nipple has several small openings arranged radially around the tip of the lactiferous ducts , from which milk is released during lactation . The other small openings in the areola are sebaceous glands , also known as areolar glands . The areolae can range from pink to red to brown to dark brown or nearly black, but generally tend to be paler among people with lighter skin tones and darker among people with darker skin tones. A reason for
16-427: A columnar epithelium supported by myoepithelial cells . Prior to 2005, it was thought within the areola the lactiferous duct would dilate to form the lactiferous sinus in which milk accumulates between breastfeeding sessions. However past studies have shown that the lactiferous sinus does not exist. The columnar epithelium plays a key role in balancing milk production, milk stasis and reabsorption. The cells of
24-457: A little above the breasts' contour. Pregnancy can cause enlargement of the Areola tissue and of Montgomery glands or tubercles. Breastfeeding by the baby stimulates slowly and rapidly adapting mechanoreceptors that are densely packed around the areolar region. Paget's disease of the breast is a malignant condition that outwardly may have the appearance of eczema , with skin changes involving
32-405: Is around 28.0 mm (1.1 in). Sexually mature women have an average of 38.1 mm (1.5 in), but sizes can exceed 100 mm (4 in). Lactating women, and women with particularly large breasts, may have even larger areolae. A function of the specialized dermis of the areola is to protect the regular breast skin from wear, cracking , and irritation. Infants sometimes create trauma to
40-533: The areola and nipple. Lactiferous duct Lactiferous ducts are ducts that converge and form a branched system connecting the nipple to the lobules of the mammary gland . When lactogenesis occurs, under the influence of hormones, the milk is moved to the nipple by the action of smooth muscle contractions along the ductal system to the tip of the nipple. They are also referred to as galactophores , galactophorous ducts , mammary ducts , mamillary ducts or milk ducts . Lactiferous ducts are lined by
48-445: The columnar epithelium form tight junctions which are regulated by hormones and local factors like pressure and casein content. Prolactin and/or placental lactogen are required for tight junction closure while progesterone is the main hormone preventing closure before birth. The majority of breast diseases either originate from lactiferous ducts or are closely related. The high susceptibility to benign and malignant diseases
56-509: The differing color may be to make the nipple area more visible to the infant. Hyperpigmentation occurs in most women during the second stage of pregnancy, leading to a temporarily darker shade. The size and shape of areolae and nipples are also highly variable, with those of women usually being larger than those of men and prepubescent girls. Human areolae are mostly circular in shape, but many women have large areolae that are noticeably elliptical . The average diameter of male areolae
64-450: The nipple and areolae by latching-on . Rated according to the Tanner scale of female physical development, the areolae enlarge during stage 3, but they show no separation of contour. During stage 4, the areolae and papillae rise above breast level and form secondary mounds. By stage 5, the breasts have fully developed. As this has resulted in recession of the areolae, the papillae may reach
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