"Whether you're shopping in a big department store or an intimate boutique, you should take the time to adjust the bra yourself or get properly fitted," says Lauren Blankenship, who owns the New York lingerie boutique Bodyhints . "Bra cuts vary wildly across manufacturers, so we send our trained staff into the dressing room with customers, because most bras are adjustable in at least two places — the back and shoulders. A bra might not seem to fit at first, but often if there's help with the adjustment, it will."
Measure yourself. With a bra on, measure yourself tightly around the top of the rib cage just beneath the bust. If it's an odd number of inches, add 5 to find your bra size; if it's even, add 4 (so if you measure 29, your bra size is 34). For your cup size, measure around yourself again, but this time place the tape measure loosely over the fullest part of the breast. Subtract the first measurement from the second. A 1-inch difference is an A cup; 2-inch difference = B cup; 3 = C; 4 = D; 5 = DD; and 6 = DDD or E.
A bra should lie flat. If your cup wrinkles on the side, you need to go down a bra — not a cup — size. And the hort piece of fabric between the breasts should be flat against your body. To make sure you put the bra on correctly, put the straps on first, then lean forward into the cups before you fasten the hooks.
The cups should hug your breasts. Your cup should be full, hugging the outer edges of the breast. If your breasts spill out from the sides or over the top of the cups, you may need a larger cup size or a cup with more coverage on the sides or top. If you favor soft cups, make sure no fabric bunches at the nipple. (Softer fabrics tend to fold on themselves.) For molded bras, be sure your breast fills the cup entirely and there isn't empty space.
Straps should be comfy but should not fall down. A strap should do its work but not cut into your skin. If your straps fall down, even after the right adjustment, your breasts may not be filling out the top of the cups and you should go down a cup size. "But if straps leave marks, it doesn't always mean they're too tight. You may need a more supportive bra," Blankenship adds. "And if the bra rides up in back, try a tighter hook or loosen the straps. If neither works, go down a bra size." Your bra straps are the right length if your bra is level across your back and not too tight when using the middle hook. Your bra, in front, should lie flat against the middle of your chest, and the back strap should rest under the lowest part of your shoulder blade.
The underwire debate. Underwires are found in 90 percent of bras made today, and should end at the side edge of your breast. "Some years ago, studies suggested that underwires might have been implicated in the formation of breast cysts and possibly breast cancer," Blankenship says. "But what they found was that women were wearing underwire bras that fit terribly. So over time the body was reacting. It's essential — with all bras — that they be fitted correctly."
Know your cups. If you're shopping for a cup size larger than B, try underwire soft cups, which offer support and will give you a natural, unsculpted line. Full coverage, molded-cup underwire bras are smooth and provide a professional look but may be stiff. Demi cups, which show the top of the breast, are found in soft or molded cups and usually have underwires. Rules of thumb: Define your breasts with molded cups, boost your breasts with demi cups and make your breasts look larger with padded cups.
Smooth, silky bras look best under all fabrics.
Match bras to your skin tone, not to the color of the garment you're wearing.
If you have large or small breasts, shop in specialty lingerie stores or boutiques. Not only will you be personally fitted, but you'll also have much more of a selection. Department stores commonly stock their greatest assortment of styles in medium sizes.
Get fitted every year, says Blankenship, even if your weight doesn't change.
And now, the $10,000, time-honored bra question: Will wearing bras prevent you from sagging? "My instinct tells me anything that helps against gravity is the right thing," Blankenship says. "But while it's impossible to know scientifically, beautiful bras make us feel beautiful. And that's always good."