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My Breasts Are Different Sizes – Am I Normal?

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My Breasts Are Different Sizes – Am I Normal?

May 15, 2018

From Downton Abbey to “Abby Normal”— Dr. Kirtly Jones explains the variations in women’s breasts and how cultural, ethnic, and developmental differences influence the perceptions of what constitutes normal. She gives suggestions and guidelines for those who may want to change the size of one breast. She also discusses whether the size discrepancy has any effect on the breasts’ function.

Episode Transcript

Announcer: Questions every woman wonders about her health, body, and mind. This is "Am I Normal?" on The Scope.

Interviewer: Am I normal? Today we are talking with Dr. Kirtly Jones, the expert on all things woman. The situation is, I have one breast that's bigger than the other. Am I... is that weird?

No Woman Is Completely Symmetrical

Dr. Kirtly Parker Jones: Well, it turns out that no woman is completely symmetrical. Even women who have had their breasts enhanced will not be completely symmetrical, just because the nature of who they were before they had the add-ons.

Breast Development

So there are two breast buds, they start growing at the very beginning of puberty. Sometimes one grows faster than the other for reasons we don't particularly understand. Occasionally, there are women, and this is quite rare, where one breast bud won't develop at all. That is not normal.

Interviewer: Okay.

Dr. Kirtly Parker Jones: But being within 20 percent of volume, meaning one breast can easily be 20 percent smaller than the other. Now is this worrisome? One breast may hang a little lower, not that any young woman's breasts hang, of course, but if one breast seems to be a little lower than the other, that's also normal. It's important for adolescents to know that breast development isn't completed until about five years after the period, so no interventions should be taken for "correcting" a disparity in breast size or augmenting breast size until women are at least 17 to 18, because at that point their breasts are relatively developed. Disparity in breast size is common. Fifteen to 20 percent difference in size is common.

Interviewer: How common?

Dr. Kirtly Parker Jones: Ninety percent of women have at least that much.

Interviewer: Oh, okay, so really high.

Dr. Kirtly Parker Jones: A very high percent of women have 10 to 15 percent disparity in breast size. They may only notice it when they are in their bra and notice that the bras, which are designed to be symmetrical...

Interviewer: Of course.

Dr. Kirtly Parker Jones: ...may feel a little differently, one versus the other. Or the cleavage may be pushed over toward the middle a little bit more than one side or the other.

What's Normal for Breast Size?

Now what about breast size? What's normal for breast size? Well every woman who walks down the street can tell that the range of normal from A cup to DD cup is all within the range of normal. Now what makes large breasts different than small breasts isn't the amount of breast tissue, isn't the amount of tissue that is able to lactate or produce milk during pregnancy, its how much fat is in the breast. So some women develop and deposit fat in their breast more than others.

It is not common to find a very slender woman, with no hips and big breasts, because we tend to put fat in our breasts and our hips somewhat equally. But very slender women may not have that much breast development either. Breast development is also different based on race. So Asian women will have smaller breasts than Caucasian women. The range of normal from A size cups to DD size cups, that's a very large range, and they are all within the range of normal.

Fashion comes and goes. During the 20s, with those really straight shifts, those really straight dresses that we all saw on Downtown Abby, no DD cups were going into those. Now we all know that Dowager Duchess, who had quite large breasts, and the kinds of dresses that she wore. But the beautiful young women were all A cups and flat as can be, and women also bound their chests so that they could be a little flatter in those really straight dresses.

Can You Enlarge Your Breasts Naturally?

Interviewer: Okay, so I have a question, and I'm going to ask this for all the ladies out there that have this question. Is there any way I can naturally change the size of my breast? Or do I have to go get them fixed?

Dr. Kirtly Parker Jones: Well, the best way to naturally, and there's a little chuckling in the room, the best way to make your breasts be a little bit larger is to be pregnant, however...

Interviewer: That's not an option.

Dr. Kirtly Parker Jones: Yes, pregnancy and breastfeeding makes your breasts larger. After breastfeeding, though, many women find that their breasts are actually smaller than they were before they were pregnant. Now you can always gain a lot of weight, and hopefully if you have a tendency to gain weight by putting fat in your breasts, your breasts might be getting larger, but at the expense of your hips and your thighs and your belly. I don't think that's worth it.

Interviewer: That doesn't sound like a good idea.

Dr. Kirtly Parker Jones: So although there have been many breast augmentation vitamins or exercises, in fact, exercises just increase the size of your pectoral muscles, which lie underneath your breasts. And women have a difficult time getting huge pecks. So getting pecks that are really big to put your boobs on is not going to be all that delicate. I would say that larger breast size for women who are small breasted, consider it fashionable, spend more time watching Downtown Abby. Spend more time running, in which case you will certainly appreciate your breast size or take up a little archery.

The term "Amazon," which is not just a very large distribution company, refers to a tribe of women who were a mezos, without Scota breast, and they took off the breast that was in front of their arrow so they could be better huntresses, so Amazon was a single breasted group of women hunters who took of a breast so they could hunt better. So for all of you small breasted women, well this is mythological of course—so all you small breasted women, spend some time in Downtown Abby, run a little bit more and you'll appreciate your breast size, or think about taking up archery.

Interviewer: My mom says it's actually nice when you have the smaller breast because when you grow older, your breasts aren't going to sag.

Count Your Breast Blessings

Dr. Kirtly Parker Jones: Absolutely, so that's another thing to... count your little breast blessings all you small breasted women, because you have quite a few breast blessings. And those of you large breast women, count your breast blessings too. It's better to count your blessings than to add or subtract from what you were given. Unless you were well outside the range of normal. So our cup size that are fashionable or desirable depends on your ethnicity, your race, the culture of the times, but between A and DD, ladies, you're all normal.

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updated: May 15, 2018
originally published: June 19, 2014