11/25/2014 11:26 am ET Updated Jan 25, 2015

The Big Bra Fit Lie (or Why Size Doesn't Really Matter)

Got bra fit problems? It's not your fault.

Sure, women's breasts are constantly changing and moving around on our chests. So it's easy to blame ourselves when a bra doesn't fit right. But let's not forget how bras are made, sized, and sold. Turns out we may wear more than one size, depending on the make and model.

Before you go shopping for your next bra, take into account the following:

1) There's more than one bra style to consider. Like boobs, bra styles come in all sorts of shapes. A push-up bra with a smooth, molded cup lifts breasts up into round mounds. A cut-and-sewn lace bra directs boobs front and center or into a point. A balconette separates breasts and makes the upper half (or "muffin top") more prominent. Add in unique boob shapes and you're bound to have bra fit problems, no matter the "right" number/letter size.

2) Bra brands use different methods to measure you. The measuring tape, and how it's used, isn't precise. Perfect fit is more trial and error, given all the different breast shapes and body types. Some brands and fitters measure you while wearing a 'fitting bra.' Others use the much maligned +4 bra fitting method to come up with your ideal size. If you're buying more than one style or brand (especially if made outside the US), you'll want to look at manufacturer or international fitting charts. Your number/letter size may not be the same in every bra.

3) Bra design, quality, and quantity of materials vary widely. Think about all the pieces that go into a bra: underwire, lace, padding, wide or thin straps, one or multiple hooks, etc. etc. Bras are subject to the same rules as the rest of the fashion world. Some clothes are made of higher quality fabrics or are so well-constructed, that they fit you like a glove. Others fall apart after one washing. The same holds true of bras. Cheaper materials, especially when asked to support the weight and motion of your boobs, won't wear as well. And before you know it, your "right" size is causing bra fit problems.

4) Cup size is not the same across bra bands (or why E can equal C). Sister sizing is term used to describe the way cup volume changes over the length of a bra band. It's another reason why your letter/number can vary. For example, the volume of a 34D can equal the volume of a 32DD or E (again, depending on brand) and a 36C. If your bra fit problem includes wearing too big a band, you're told to go down a band size and up a cup size. If you just reduce the band size, you'll end up in a smaller cup.

Given the realities of the bra industry, it's no surprise some 80 percent (and likely 100 percent!) of women wear the "wrong" size. Changing breast flesh matched with inconsistent styles, quality, and sizing make it hard to avoid.

Maybe it's time we all stop talking about "right" or "correct" size and accept a more fluid "Bra Zone." We can't find the perfect bra if we aren't open to trying a range of brands and styles.

My bra zone extends from 34D or DD to a 32E or F. My boobs fit best into a cut-and-sewn and demi-cup styles. It's less about the number and more about how the bra fits and makes me look in (or out) of my clothes. After all, no one sees the size anyway.

What about you? Do you wear the same size across all bra styles and brands? Do you think the bra industry could do more to address these bra fit problems?

This article first published on The Breast Life.