We’re betting that you and your girls are pretty tight. But if one seems to flaunt a size DD while the other is a humbler size C, don’t panic! You’re not the only one.
“It is actually more common for women to have different breast shape and size than absolutely symmetrical breasts,” Nazanin Khakpour, MD, FACS, a surgical oncologist specializing in breast cancer at Moffitt Cancer Center, told SELF. “They are sisters, not twins.”
So rest assured that your asymmetrical breasts are completely natural. But why is one bigger than the other to begin with? Like many other mysterious things about your body, it depends. (Find out how your breasts change as you age.)
Uneven breasts are often inherited, according to Sherry Ross, MD, a women’s health expert at Providence Saint John’s Health Center in Santa Monica. So if your mom and grandmother’s breasts are two different sizes, it’s likely that yours will be, too.
It could also be a matter of weight loss or gain. Because your boobs are partially made up of fat (along with connective tissue and milk ducts), their size can change as your weight does. But you don’t always gain or lose weight evenly across your entire body. Same goes for your breasts; one could lose or gain more fat than the other.
What’s more, uneven breasts might be a sign of condition like scoliosis (a curvature of the spine) or an abnormal chest wall. But don’t worry, genetics and weight change are much more common causes of asymmetry.
You should still pay attention if your breasts suddenly become asymmetrical, especially if other symptoms—such as skin retraction or the thickening, dimpling, or a change in color of your breast—show up, too. “That should be brought to the attention of a physician immediately as these may be the first presentation of certain types of tumors,” Therese B. Bevers, MD, professor of clinical cancer prevention and the medical director of the Cancer Prevention Center at MD Anderson Cancer Center, told SELF. Watch out for the other signs of breast cancer you might be ignoring.
But again, this shouldn’t be cause for concern. “It’s most likely weight gain or loss,” Dr. Bevers said. All the same, it can’t hurt to get them checked out! And while you’re at it, don’t miss 13 more things your breasts won’t tell you.