Intermammary cleft

Intermammary cleft
Anatomical region of woman's cleavage
Details
Latin	sulcus intermammarius
Anatomical terminology []

In female human anatomy, the intermammary cleft or intermammary sulcus or sulcus intermammarius of a woman is delineated by where the fatty portions of each breast sits in relationship to the sternum (or breastbone). It divides the two mammary complexes that consist of two bodies of fatty pads, glandular tissues of mammary glands, connective tissues, and skin, as well as two duct systems (lactiferous duct of lymphatic vessel) and lobule alveoli emanating from two nipples. Lymph vessels can ventrally extend as far as the intermammary sulcus.

The International Federation of Associations of Anatomists (IFAA) uses the terms "intermammary sulcus" or "intermammary cleft" when referring to the area between the breasts not including the breasts. In popular usage the area is commonly referred to as a woman's cleavage, especially when exposed by garments with low necklines.

For legal purposes it was noted by the United States federal courts that "" and "cleavage of the female breast" are so imprecise as to provide no guidance in defining them. Medically, the "width" of a woman's cleavage is determined by the attachment points of her breast tissue to the periosteal tissue covering her sternum and is also defined somewhat by the medial attachments of the pectoralis major muscle when implants are in the sub-muscular position.

Plastic surgeon Alan Matarasso said, "Ergonomically speaking, cleavage equals the position of the breasts on the chest wall." The skin of the cleavage area is frailer than the skin of the face as it has fewer oil glands, and may show loss of elasticity sooner.

Poikiloderma of Civatte, a condition of dilated blood vessels and red to red-brown spots, is common to the upper part of the cleavage, especially for those who wear a sports bra or push-up bra for prolonged periods, and commonly affects fair skinned middle-aged to elderly women.