The Sizing of Underwire & Wire Free Bra Cups - It's Really about Projection

Ah, the alphabet soup of cup sizing. Though very systematic up to a D cup size, it becomes a complete mystery further up the cup sizing chart. So, what is going on with cup sizing? And, how does a woman know if she needs a new cup size?

Let's start with some basic information about bra cup sizing. The industry standard for bra sizing today was invented back in 1928. And back then, it only went up to a D cup size. So right there, you can see why the system could have several issues. Anyway, an A cup was designed to hold 8 fl. ounces, 13 fl. ounces in a B, 21 fl. ounces in a C and 27 fl. ounces in a D cup.

Since then, people have tried to take the basic measuring system and extrapolate it to larger breast sizes. This really doesn't work. Consequently, a woman can be measured but the result will not match what her true size is. She then becomes frustrated.

So, let me share with you what is going on with cup sizing. The first and most important thing to know is that a cup size on one band size is not equal to the same cup size on another band. In other words, a D cup on a 34 band is smaller than a D cup on a 38 but larger than a D cup on a 32 band. The number one mistake women make in changing their size is to go up a band size while keeping the same cup letter. When they do this, the cup size increases even though the letter stays the same.

Why do they do this? The answer is that a cup size is actually a measure of how far your breasts project from your chest wall - not the volume. When you are measured, if your breast circumference increases by one inch, you need to go up a cup size. This makes sense when you think about the measuring system. You take your breast circumference measurement and subtract your band measurement. The difference determines your cup size - 3 inches = C cup, 4 inches= D cup, etc.

Now, let's think about what happens when you increase your band size. Going back to the measuring system, you deduct your new band size from your breast circumference. Your band size is larger thus reducing the difference between your two measurements by an inch or two. If your breasts haven't grown, but your underbust measurement has, going up a band size also means you need to come down at least one cup size or your cups will be too large. So, for example, going from a 38D to a 40 band, you will need to come down a cup size to a 40C if your breast size has not increased.

I mentioned earlier that the traditional system of measuring for a bra size starts falling apart after D cup sizes. This is true because the larger breasts tend to sag. So, breasts need to actually be held up for the breast circumference measurement to be accurate. And even then, it's going to be difficult to get the right size based solely on the measuring system. This is why I recommend women with a D+ breast size get into her best fitting bra and figure out her proper size based considering what seems to fit right and what doesn't.

One final point on cup sizing. A woman's breast has a weight range of 8 ounces to 14 lbs. and we demand that a 1.6 ounce bra support all the different shapes and sizes. It's really rather amazing if you think about it.

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10/20/2008 2:23:50 PM
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In 1999, Tomima Edmark realized there was a gap in the options women had to buy lingerie; our choices were department store, lingerie boutique or mail order. Why shouldn’t we have the same ease buying bras that we had for, say, tee shirts or music? An entrepreneur with a series of unconventional successes, Tomima turned ...
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