If each of your breasts has the same size, you're one of the very lucky few.
Why is the left breast usually bigger?
Women know how difficult it is to find a bra that is just right. The problem is very often that the two breasts are of different sizes. Even though humans like symmetry and even though the human body appears symmetrical at first glance, it is not so. Nature creates a balance by asymmetry. Many people have one leg longer than the other and many women have their left breast larger than the right one.
Some claim that it has to do with what hand you write with. If you are right-handed, the right breast is supposedly bigger. Others are convinced that the left breast is bigger because we have our hearts on the left side of our bodies. These are all unscientific beliefs.
Should you deal with asymmetrical breasts by means of cosmetic surgery?
According to plastic surgeons who studied the breasts of 600 women, most women have their left breast bigger than the right one. It is often the case that breasts do not develop simultaneously. One of them develops sooner and to a greater extent. These asymmetrical breasts burden some women so much that they decide to have cosmetic surgery to increase the size of one breast or decrease the size of the other.
Women who are uncomfortable with getting cosmetic surgery can also help themselves in less painful ways. Choosing the right bra can help greatly. Padded bras (the padding can also be removed) are perhaps most appropriate for such cases.