[kurious kat]

Originally Posted by hornyyoungslut

Just a random question here: How the fuck do you not realize your breasts grew 3 cup sizes up?

This is actually a really common confusion about how bra sizes work!

The number represents the band size, which should be your ribcage measurement (just under the breasts) in inches, plus 4 -- or 5, if the measurement was an odd number.

The cup size is then determined by the difference between the band size and your full bust measurement (over your breasts themselves). A C cup, for example, means the breasts themselves measure about 3" bigger than your band size, while a D cup is 4", and an E cup (in Europe, or DD in the US and UK) is 5".

So while it sounds like a 32C bra is much smaller than a 30E, if you do the math, you discover...
32 C: Underbust = 27-28 inches; breasts = 35 inches
30 E: Underbust = 25-26 inches; breasts = 35 inches

Since most non-specialty bras run 32A to 40DD in stores at best, it's not uncommon for women to assume they have a 34 to 38 band size, since that's what's most commonly available, and find the closest cup size from there. But since the band provides most of the support for the breasts, and the cup size just indicates how deep they are vs. the band, switching to a new size can be more comfortable.