Jockey International has spent eight years developing a new measurement system, which the company says takes into account the shape of a woman's breasts, not merely bust size.
The bras are a mass-market answer to custom fittings that have become increasingly popular in boutiques and high-end department stores, the New York Daily News reported.
Whether Jockey's approach will catch on is uncertain. But the Jockey Bra, formally introduced Thursday, is nonetheless another step in the evolution of the modern brassiere.
The pitch may appeal to women newly conversant in fashion.
"People are becoming more knowledgeable about fashion minutiae, and they're focusing on things like fit," Valerie Steele, director of the Museum at the Fashion Institute of Technology, said.
It may seem surprising but the lingerie industry itself pushes the notion that off-the-shelf bras often don't fit well.
The bra manufacturer Wacoal, for instance, says about eight out of 10 women wear the wrong size.
Until now, however, standard sizes have barely changed, although the range has expanded.
Cup sizes are based on two measurements - the breast at its fullest point, minus the rib cage measurement.
If it's a one-inch difference, it's an A cup; a two-inch difference, a B cup; and so forth.
That approach, Jockey executives say, doesn't account for different breast shapes.
Jockey began the project by scanning 800 women, getting "data points about all of the different measurements of a woman's torso and the breast size," Sally Tomkins, a senior vice president said.
Researchers followed women in their homes as they chose bras and dressed, and heard "complete dissatisfaction about every aspect of the bra purchasing process, from the inaccuracy to the way you get measured," Dustin Cohn, the company's chief marketing officer said.
In the end, Jockey came up with 10 cup sizes.
"Our bras don't necessarily get bigger, bigger, bigger, but in different proportions - they get larger, but in different shapes," Cohn said.
To fit the bras, Jockey uses a kit with 10 plastic cups in varying shapes, along with a measuring tape.
Customers are meant to try on the cups and see what works best, then measure their rib cage.
Someone with a 34-inch rib cage and medium-size breasts might wear a 5-34 or a 6-34, for instance.
