Interesting Facts About Breasts

Breasts vary in size, density, shape, sag and position on a woman's chest, and their external appearance is not predictive of their internal anatomy or lactation potential. The natural shape of a woman's breasts is primarily dependent on the support provided by the Cooper's ligaments and the underlying chest on which they rest (the base). Cooper's ligaments, also known as the suspensory ligaments of Cooper, suspend the breasts from the clavicle and the clavi-pectoral fascia. As their fibers run around and through the breast, these ligaments support the breasts in its position on the chest wall and maintain their normal shape. The breast is also attached at its base to the chest wall by the deep fascia over the pectoral muscles. In a small number of women, the frontal ducts (ampullae) in the breasts are not flush with the surrounding breast tissue, which causes the sinus area to visibly bulge outward.
Some breasts are high and rounded, and protrude almost horizontally from the chest wall. Such high breasts are common for girls and women in early stages of development. The protruding or high breasts are anchored to the chest at the base, and the weight is distributed evenly over the area of the base of the approximately dome- or cone-shaped breasts.
In the “low” breast, a proportion of the breasts' weight is actually supported by the chest against which the lower breast surface comes to rest, as well as the deep anchorage at the base. The weight is thus distributed over a larger area, which has the effect of reducing the strain. In both males and females, the thoracic cavity slopes progressively outwards from the thoracic inlet (at the top of the breastbone) above to the lowest ribs which mark its lower boundary, allowing it to support the breasts.
The inframammary fold (or line, or crease) is an anatomic structure created by adherence between elements in the skin and underlying connective tissue and represents the inferior extent of breast anatomy. Some teenagers may develop breasts whose skin comes into contact with the chest below the fold at an early age, and some women may never develop such breasts; both situations are perfectly normal. The relationship of the nipple position to the fold is described as ptosis, a term also applied to other body parts and which refers in general to drooping or sagging. Due to breast weight and relaxation of support structures, the nipple-areola complex and breast tissue may eventually hang below the fold, and in some cases the breasts may extend as far as, or even beyond, the navel. The length from the nipple to the sternal notch (central, upper border) in the youthful breast averages 21 cm and is a common anthropometric figure used to assess both breast symmetry and ptosis. Lengthening of both this measurement and the distance between the nipple and the fold are both characteristic of advancing grades of ptosis.