But how much do we really know about this fascinatingly female body part? Did you know that one in 50 women may have an extra nipple (or two)? Or how about that in most women, it's the left breast that's slightly larger than the right? And did you know that the average woman in the U.S. wears a C cup? Or that breast implant surgery has surged 40 percent in the last decade? Want to know more? Check out 15 more fascinating facts about breasts in the infographic below.