Cross section of the breast of an adult, female human
Inframammary fold (IMF), inframammary crease or inframammary line is the feature of human anatomy which is a natural boundary of a breast from below, the place where the breast and the chest meet. The choice of the term depends on the prominence of the feature. It is also sometimes called inframammary ligament. From the cosmetological point of view it is an important aesthetic component of the breast, which should be taken into the consideration during various kinds of breast surgery. 
Histologically, it was revealed that the inframammary fold is an intrinsic dermal structure consisting of regular arrays of collagen held in place by a specialized superficialfascial system. The fold is formed by the fusion of the superficial and mammary faciae. 
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