How important is BWD in choosing implant size?

I measured 12.2 cm but my surgeon is recommending an implant size that is designed to fit a patient with a 12.5 cm BWD according to the mentor chart. I'm told that choosing the smaller implant size (255cc moderate for 12.2cm) will result in more of a valley look between the breasts but I'm worried the 277cc moderate will be too wide for my body and result in overdoing the side boob and potentially stretching my skin. Thoughts / advice?

Doctor Answers 14


The more I do breast augmentations the less I rely on BW.  Women in LA often don't want small implants.  If I relied on BW for selection I would be placing high profile implants in most women.  Thankfully I don't because high profile implants generally look terrible and sacrifice cleavage for projection. 

Beverly Hills Plastic Surgeon
4.9 out of 5 stars 30 reviews

Importance of Base Width Measurement in Breast Augmentation?

Base width is important as a starting point in choosing an implant for augmentation. As a general rule it is best not to significantly exceed one's base width measurement as it predisposes you to problems of a palpable or visible implant and implant malposition. However there are some circumstances in which that rule may be violated such as the patient with a constricted breast. So it's not a firm number. In addition, the measurement of base width is somewhat subjective, and many surgeons will vary from that initial measurement based on considerations such as tissue thickness, shape of native breast tissue, desired appearance after augmentation, etc. 

If your surgeons initial measurement of BWD was 12.2, and they suggested an implant of 12.5, that is not really a significant increase (3 mm) from the original measurement. It may have been the case in your situation that you had a wider space between your breasts, so your surgeon was choosing an implant that would help narrow that space a bit (within reason). Remember that with a round implant increasing the base diameter to get some improvement in the space between the breasts will also result in some widening laterally and create more "side boob". If you are concerned about that, then the solution is easy, simply choose a higher profile implant which will give you the same volume without the increased base width. I have found that the "moderate" profile in Mentor implants is really excessively wide for most patients and that one on their higher profile implants tend to be more appropriate for most patients.

To some some extent it is a matter of the patients personal preferences, so it is important for you to be clear with your surgeon about what you like and don't like. What works for many patients is to try to find an overall volume that you feel is conformable, and then look at the various profiles to choose a base width that fits your dimensions. 

BWD is really important

BWD is the most important measure and should never be exceeded if you want a good looking result (with a few exceptions). That is why there are other profiles, if you have 12.2 cm of BWD at least you should choose a high profile implant. 

Get a second opinion.

Luis Eduardo Redondo, MD
Dominican Republic Plastic Surgeon
5.0 out of 5 stars 17 reviews

Breasts width dimensions is important for the cleavage that you desire.

For each woman there is an ideal BWD.  That measurement will vary from person to person because we are all built differently.  Its important to measure the maximum base width that will fit in the patient.  You would want to chose an implant that is close to the base width.  Its the width of the implant that is important for the closeness of the cleavage.  You should not exceed the maximum base width or you will be at risk of developing an uniboob.  Once the base width is selected you then chose the projection the patient desires to achieve the volume she wants.  That's why there are low, medium high and ultra high projections.  Using computer simulation such as the Vectra 3D helps the patient see the difference prior to surgery.  Also using the Mentor implant sizing system helps the patient feel the weight and size of the breast.  By using these methods my patients are never wrong with the implant sizing process. 

Benjamin Chu, MD, FACS
Honolulu Plastic Surgeon
4.8 out of 5 stars 79 reviews

Breast Base Width

Thank you for your question. Your breast base diameter is very important in choosing the correct implant size for your body. Exceeding that measurement can sometimes result in an augmentation that is not frame appropriate. I would recommend speaking with your Board Certified Plastic Surgeon before surgery and also doing 3D Vectra Imaging if available to you. Best of luck to you.

Ed Breazeale, Jr., MD
Knoxville Plastic Surgeon
4.9 out of 5 stars 8 reviews

Implant Sizing for Breast Augmentation

This is a good question as a lot of patients do not understand that implant sizing is not like it used to be.  In the past, all we had was essentially round balls that, as they got wider or increased in diameter the volume went up.  We then had different profile implants that allowed us to consider different volumes with similar diameters of implants.  Now with the gummy bear shaped implants we have a number of considerations including volume, shape, projection or profile, height and width of the implant.

Width if the implant is important but when considering this measurement, you do not need to worry too much about differences on a few millimeters as this is very small and a range of 10 mm will make very little difference in the outcome.  Similarly, 20 to 30 cc difference in volume, which is only 2 tablespoons will have very little impact on the outcome.  

If you tried the implants under a sports bra and liked that you should like your results with either size.

I have added a video about implants for you as well as a web reference that may help.

Brian Windle, MD
Kirkland Plastic Surgeon
4.9 out of 5 stars 50 reviews

How important is BWD in choosing implant size?

Fitting the implant width to the breast width is very important, but there is usually a range of widths that will "work" and give good results. I usually measure the breast width (or desired width in a narrow-based constricted breast) and estimate the range from narrowest to widest implant that will appropriately fit into this breast, and then see what volume a patient desires by having her try sizers on in a bra. If a patient wants a larger size that in a moderate profile implant will be too wide, they may need to go to the narrower high profile implant. In your case, if indeed your 12.2 cm measurement was in fact accurate "to the millimeter", which it rarely is, then realize that the difference between your breast width and a 12.5 cm implant is only 3mm. Look at a ruler and see how small 3 mm is, and you can see that this probably will not make much difference at all in creating more "side boob", as you put it, or overstretching your skin.

Breast width in choosing implants

The width of a breast is a very important measurement for breast augmentation. That being said, there are 3 factors in choosing your implants - the type of result that you are looking for (natural vs. augmented), your breast measurements (including width & nipple distance from the areola), and the size that you liked when using the sizing system. All of these factors come into play when choosing the implants that are right for you.
The difference between a 12.2cm and a 12.5cm implant, however, is so negligible that it will not make a difference. 3mm will not give you "side boob". The difference of 22cc of the implants is also fairly small (a shot glass is 30cc). So, you would probably fit both implants very nicely. Discuss your concerns with your plastic surgeon to make sure you are comfortable before you proceed with surgery.

How important is BWD in choosing implant size?

Thank you for your question.  BWD is an important factor in choosing your implant size, ensuring that it's not too wide or narrow within your breasts.  Once measured, it serves as a guide for implant selection and there is some flexibility beyond that depending on several other factors.  However, you don't want to deviate too far beyond this measurement.  Be sure you consult with an experienced board certified plastic surgeon to help guide you further.  Best of luck!

Zachary Farris, MD, FACS
Dallas Plastic Surgeon
5.0 out of 5 stars 14 reviews

Breast width diameter and implant size

Thank you for your question.  Breast diameter is a very important factor when choosing your implants.  However, many women have a breast diameter that is too narrow, particularly if they have very little breast tissue.  I measure what I would call the "ideal" breast diameter for a given woman's chest.  In many cases your breast implant diameter may be slightly larger than the actual breast diameter in order to give optimal cleavage toward the middle and the outside (side boob).  Obviously, there are limits to how wide an implant should be in order to avoid a symmastia (uniboob) or to much lateral fullness that gets in the way of your arm.  In your case, I doubt 3mm would make a significant difference, but best to check with your surgeon if you feel uncertain.  Good luck. 

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.