Breast asymmetry is caused by a congenital malformation in which there is a difference in size between the two breasts. This difference is noticed as a disproportionate size of only one breast, when the shape of the breast is different and/or when one breast show ptosis. With the aim of preventing other diseases, often a mammogram is performed. Breast asymmetry can be caused by excess fat, glands or both. Depending on the degree of asymmetry the specialist will choose the kind of treatment, which could be breast augmentation with implants, breast lift or mastopexy, or breast reduction.