Add to this the many different styles of bras and the lack of standardization between brands, and one can see why finding a comfortable, well-fitting bra is more a matter of educated guesswork, trial, and error than of precise measurements.
at a retailer offering the widest possible selection of bra sizes and brands.
Generally, if the wearer must continually adjust the bra or experiences general discomfort, the bra is a poor fit and she should get a new fitting.
produce inconsistent measurements of the same person.
Since a brassiere must be laundered frequently, easy-care fabric was in great demand.
Pendulous breasts can make it difficult for a person to properly fit a bra.
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.
To help women meet the perceived ideal female body shape, corset and girdle manufacturers used a calculation called hip spring, the difference between waist and hip measurement (usually 10–12 inches).
The man-made fibres were quickly adopted by the industry because of their easy-care properties.
In a study conducted in the United Kingdom of 103 women seeking mammoplasty, researchers found a strong link between obesity and inaccurate back measurement.
They concluded that "obesity, breast hypertrophy, fashion and bra-fitting practices combine to make those women who most need supportive bras the least likely to get accurately fitted bras." One issue that complicates finding a correctly fitting bra is that band and cup sizes are not standardized, but vary considerably from one manufacturer to another, resulting in sizes that only provide an approximate fit.
Some French manufacturers also increase cup sizes by 3 cm.), while most Americans can find bras with cup sizes ranging from A to G.