The breast is a normal part of the human anatomy. It exists in both women and men. The breast anatomy will be described in layers from superficial to deep.

Breast skin

The breast area is covered by skin. The skin layer of the breast has the skin as well as superficial nerves,and blood vessels. The deepest layer of the breast skin is the dermis. This skin layer is the strength of the skin. Different women have different thicknesses of the dermis.The thicker the dermis, the stronger the skin usually is. Also in the the skin are fibers that stretch called elastin. The dermis and elastin content in the skin will determine how much the skin will stretch and then return to its regular position. If breast skin is expanded over a period of time,like in pregnancy, the breast skin may become thinner and the elastic component of the skin may not be enough for the skin to return to its earlier shape and position. When this occurs the breast skin will droop or sag. When a breast expands too quickly for the skin to adjust to the increase in size, a stretch mark may occur. A stretch mark occurs when dermis of the skin tears and this can be seen through the thinner outer layers of the skin.

Also located on the most superficial layer of the breast is the nipple and areola. This colored tissue is different from the other skin areas because it has the breast gland structures and it is usually thinner and stretches more than the skin. Through this nipple and areolar area the women's breast milk may be delivered to the baby.

Breast fat and gland

Beneath the skin is the gland and fat of the breast. The ratio of gland percentage to fat percentage is different for every women. The age of the women usually affects the amount of fat and gland that are actually in the breast. Breast gland is usually more firm feeling. As women age, the amount of breast gland usually increases or persits until the age of 30's and then starts to decline. As the breast gland volume decreases, the breast will become smaller unless the amount of fat increases.

Traveling through the breast gland and fat are nerves, blood vessels, and lymph nodes. The breast and fat of the breast lie on top of chest wall muscles and the rib cage.

Inframammary Fold of the breast

This breast fold is usually where the 'underwire' of a bra sits. It is where the breast skin appears to rejoin the chest wall skin. Even though a woman's breast may not appear to be large enough to cause a fold or crease, the anatomical structure of the IMF still exists. The strength or development of this fold on women is variable. Some women have well developed fold structures while others are not as well formed. This is important because, the breast implant usually rests on this fold. In some women, the breast implant may be too heavy to be supported by weaker or damaged inframammary folds.When this occurs the breast implant will cause the fold to lower.

When breasts are different sizes, these folds may be at different levels. So if the IMF are at different levels, then the breast mounds will be in different positions.