Some Information About Breasts

Most of the human female breast is actually adipose tissue (fat) and connective tissue, rather than the mammary glands. There is naturally a great variety in the size and shape of breasts in women with size being affected by various factors including genetics.

The primary anatomical support for the breasts is thought to be provided by the Cooper's ligaments, with additional support from the skin covering the breasts themselves, and it is this support which determines the shape of the breasts. The breasts naturally sag through aging, as the ligaments become elongated. This process may be accelerated by high impact exercises, and a brassiere may reduce this effect by providing external support, although the health benefits of wearing of a brassiere are not universally accepted. Pendulous breasts (ptosis) are considered undesirable by some, and some older women seek cosmetic surgery to raise their busts.

A long term clinical study showed that women with large breasts can suffer shoulder pain as a result of bra straps, although it should be stated that a well fitting bra should support most of the breasts' weight on the back strap rather than on the shoulders.

As breasts are mostly composed of adipose tissue, their size can change over time if the woman gains or loses weight. It is also typical for them to grow in size during pregnancy and while breastfeeding, mainly due to hypertrophy of the mammary gland in response to the hormone prolactin. The size of a woman's breasts usually fluctuates during the menstrual cycle, particularly with premenstrual water retention. An increase in breast size is also a common side effect of use of the contraceptive pill.

There is no relationship between breast size and ability to breastfeed, and it is a common belief that human female breasts are shaped the way they are so that they can feed babies by producing milk. However, their shape is also thought to have evolved due to sexual attraction, as described above. The orb-like shape of breasts help limit heat loss, as a fairly high temperature is required for the production of milk.

In order to support the breasts adequately, a correctly sized bra must be worn and it is for this reason that breast size is typically expressed as a "bra size". Women with exceptionally large breasts may experience back pain. In some societies there is a belief amongst some that small breasts make a woman less sexually attractive. Some women suffer from insecurity about their breasts, and in some cultures a number of women who are unhappy with their size seek surgery either to artificially reduce or enlarge their breasts. The American Society for Aesthetic Plastic Surgery found that 334,052 breast augmentation procedures were performed in 2004. Some women undergo breast reconstruction after mastectomy for breast cancer, a result of the high value placed on symmetry of the human form in those cultures, and because women often identify their femininity and sense of self with their breasts.

It is typical for a woman's breasts to be unequal in size, particularly whilst the breasts are developing during puberty. Statistically it is slightly more common for the left breast to be the larger. In some rare cases, one breast may be significantly larger or smaller than the other, or fail to develop entirely.