Brassiere measurements

Determining the correct bra size (also known as brassiere measurement or bust size) is the process manufacturers engage in to design and manufacture bras that correctly fit a majority of women, and for individual women, the process of identifying a correctly fitting bra. Bra sizes usually consist of one or more letters indicating the breast cup size and a number, indicating a band size around the woman's torso. Bra cup sizes were invented in 1932 and band sizes became popular in the 1940s.

The shape, size, position, symmetry, spacing, firmness, and amount of sagging of individual women's breasts vary considerably. Manufacturers' bra size labeling systems vary from country to country because no international standards exist. Even within a single country, one study found that the bra label size was consistently different from the measured size. As a result, about 25% of women have a difficult time finding a properly fitted bra. Some women choose to buy custom-made bras due to the unusual size or shape of their breasts.

Parisienne Madeleine Gabeau received a United States patent on 21 November 1911 for a brassiere with soft cups and a metal band that supported and separated the breasts. To avoid the prevailing fashion that created a single "monobosom", her design provided "that the edges of the material d may be carried close along the inner and under contours of the breasts, so as to preserve their form, I employ an outlining band of metal b which is bent to conform to the lower curves of the breast."

The term "cup" was not used to describe bras until 1916 when two patents were filed.

In October 1932, the S.H. Camp and Company were the first to measure cup size by the letters of the alphabet, A, B, C, and D, though the letters represented how pendulous the breasts were and not their volume. Camp's advertising in the February 1933 issue of Corset and Underwear Review featured letter-labeled profiles of breasts. Cup sizes A through D were not intended to be used for larger-breasted women.

In 1937, Warner introduced its Alphabet Bra with four cup sizes (A, B, C and D) to its product descriptions. Before long, these cup sizes got nicknames: egg cup, tea cup, coffee cup and challenge cup. Two other companies, Model and Fay-Miss (renamed in 1935 as the Bali Brassiere Company) followed, offering A, B, C and D cup sizes in the late 1930s. Catalog companies continued to use the designations Small, Medium and Large through the 1940s. Britain did not adopt the American cups in 1933, but resisted using cup sizes for its products until 1948. The Sears Company finally applied cup sizes to bras in its catalog in the 1950s.

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