Will 420cc Implants Make Me Very Big?

I am scheduled for surgery in 4 days and now I am second guessing the size of implants. (pre surg nerves and size obsession) I am 5ft 115lbs, currently 34C breast diam 15cm, w/level 2 ptosis. I would like to have very large full breasts approx 34DD.I was advised implant sizes 330cc-500cc would work for me. My PS recommended 420cc moderate pr, saline under muscle. I have worn sizers in both 400&475. I love big, but dont want crazy big. Will 420cc give desired 34DD or do I need bigger implant size?

Doctor Answers (14)

Breast implant sizing


The more breast surgery I do the more I realize that there is no correlation between the size or model (profile) of implant used and resulting cup size.  This may have to do with several factors including: the amount of breast volume the patient starts with, the shape of the patient's chest wall (concave or convex), the type and model of breast implant selected (saline/silicone  and low/moderate/high profile), bra  manufacturer variance  in cup sizes, the  degree  of filling of the cup  with breast tissue,  and the subjective differences in patients perceptions of cup size. 
Much of the final “look” achieved after breast augmentation surgery  depends on several factors:

1. The initial shape, size (volume of breast tissue), symmetry of the patient's breasts. In general, the better the  preoperative breast appearance the more likely the breast augmentation “look” will be optimal.

2. The experience/skill level of the surgeon is important in determining the final outcome. For example, the accurate and gentle dissection of the breast implant pockets are critical in producing  long-term  well-placed breast implants. I personally think that these 2 factors are more important than any others, including type (saline or silicone)  or model (low/moderate/high profile)  of implant.

3. The type of implant used may  determine the final outcome, especially if the patient does not have significant covering breast or adipose tissue. For example, some surgeons feel that silicone implants have a more natural look and feel than saline implants because silicone gel has a texture that is similar to breast tissue. Each patient differs in the amount of breast tissue that they have.  If a patient has enough breast tissue to cover the implant, the final result will be similar when comparing saline implants versus silicone gel implants.  If a patient has very low body fat and/or very little breast tissue, the silicone gel implants may provide a more "natural" result.
On the other hand, saline implants have some advantages over silicone implants. Silicone implant ruptures are harder to detect. When saline implants rupture, they deflate and the results are seen almost immediately. When silicone implants rupture, the breast often looks and feels the same because the silicone gel may leak into surrounding areas of the breast without a visible difference.  Patients may need an MRI to diagnose a silicone gel rupture.   Saline implants are also less expensive than the silicone gel implants.
Other differences involve how the breast implants are filled. Saline implants are filled after they’re implanted, so saline implants require a smaller incision than prefilled silicone breast implants.
On May 10, 2000, the FDA granted approval of saline-filled breast implants manufactured by Mentor Corporation and McGhan Medical. To date, all other manufacturers’ saline-filled breast implants are considered investigational.
As of 2006, the FDA has approved the use of silicone gel implants manufactured by the Mentor Corporation and Allergan (formerly McGhan) for breast augmentation surgery for patients over the age of 22.

4. The size and model of breast implant used may  make a  significant difference in the final outcome. Therefore, it is very important to communicate your size goals with your surgeon.  In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as “natural” or “C cup” or "fake looking" or "top heavy" or "crazy big" means different things to different people and therefore prove unhelpful.
Also, as you know, cup size varies depending on who makes the bra; therefore, discussing desired cup  size may also be inaccurate.
I use  intraoperative sizers and place the patient in the upright position to evaluate breast size. Use of these sizers also allow me to select the breast implant profile (low, moderate, moderate plus, high-profile) that would most likely achieve the patient's goals. The patient's goal pictures are hanging on the wall, and allow for direct comparison.
I have found that this system is very helpful in improving the chances of achieving the patient's goals as consistently as possible.
By the way, the most common regret after this operation, is “I wish I was bigger”.

I hope this helps.

San Diego Plastic Surgeon
5.0 out of 5 stars 681 reviews

What is considered BIG for Breast Implants


420cc is about 2 cup sizes.  If you've tried the implant samples to show you what 420cc implants would look like in addition to what you already have and are pleased with what your body looks like, then I say "Go for it!" 

My only concern is how you'll feel about your choice, 10-15 years down the line, after childbirth, gravity and weight gain has hit.

Genevieve MacDonald, MD
Los Angeles Plastic Surgeon
5.0 out of 5 stars 1 review

420 cc breast implants are large on a petite 5 foot all woman


Thank you for your question. It sounds as though you have tried sizers and have a good idea of what size you want to be.

, That said 420 cc breast implants are significantly large on a petite small woman with a 5 foot frame.

If you are uncertain you need further discussion with your plastic surgeon.

Brooke R. Seckel, MD, FACS
Boston Plastic Surgeon
5.0 out of 5 stars 26 reviews

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Implant Selection Process


Unfortunately, there is not a general rule of thumb or objective criteria to implant selection.

Your plastic surgeon will perform several measurements of your chest wall and breast anatomy and determine a range of implants that both fit your chest wall and reach your desired goals.

The next step is to try on this range of implants in the office with your doctor.   The key to this success is showing your surgeon the body proportion you desire with a bra sizer and allowing your surgeon to guide you to the right implant.   It will be much easier to communicate in implant cc's than cup size when determining the appropriate implant for you.

I wish you a safe recovery and fantastic result.

Dr. Gill

Paul S. Gill, MD
Houston Plastic Surgeon
5.0 out of 5 stars 34 reviews

Make any implant size changes before your day of surgery.


Whichever implant size you felt the most comfortable with is the ones you should go with.  Make sure the size you are choosing is the one you really want.  You should call the office asap and let the office know your concerns rather than on the day of your surgery.

Otto Joseph Placik, MD
Chicago Plastic Surgeon
5.0 out of 5 stars 41 reviews

Sizing of Breast Implants


As mentioned by others, it is very difficult to translate implant sizes to cup sizes.  If you are now wearing a 34C bra and do not want to be "crazy big", you do not want to go bigger than a 420cc implant.  Not only would you be "crazy big", but it would also be obvious that you have been augmented.

John Whitt, MD
Louisville Plastic Surgeon
5.0 out of 5 stars 2 reviews

Would Will Breast Implants Make Me Very Big?


Regarding: "Will 420cc Implants Make Me Very Big?
I am scheduled for surgery in 4 days and now I am second guessing the size of implants. (pre surg nerves and size obsession) I am 5ft 115lbs, currently 34C breast diam 15cm, w/level 2 ptosis. I would like to have very large full breasts approx 34DD.I was advised implant sizes 330cc-500cc would work for me. My PS recommended 420cc moderate pr, saline under muscle. I have worn sizers in both 400&475. I love big, but dont want crazy big. Will 420cc give desired 34DD or do I need bigger implant size

THE KEY to an attractive augmented breast is picking an implant which is fully covered by YOUR current breast tissue and does not slide sideways off your chest. Your surgeon can easily tell you if your breast width matches that of the 420 or 475 cc implant. Choosing a larger implant will expose the ripples of the implant along the side and bottom of the breast.

The key to a long lasting perky breast is using the smallest implant you can put up with. You ALREADY have grade 2 sagging of the breast with your natural 34C breasts and yet you did not mention any plans to lift your breasts and correct the sagging during this surgery. Adding 420 or 475 grams to each sagging breast will increase the rate of breast sagging. Something to consider.

I would talk to your surgeon and ask him which breast implant offers the best compromise of full coverage and weight to try and get the best result.

Good Luck.

Dr. Peter Aldea

Peter A. Aldea, MD
Memphis Plastic Surgeon
5.0 out of 5 stars 58 reviews

Breast Implant Sizes


It sounds like 420 cc would be a very attractive, natural D to DD size. Don't get caught up in the #s, you can drive yourself crazy worrying about 30 cc which in reality is 6 teaspoons, and spread over a big surface area such as the breast doesn't amount to much. Most patients do wish  they would have gone bigger. However, you are also petite, so you want to see an pretty shape, with some proportionality without being over-the-top. I would trust your doctor.  You also have to realize that larger implants have more risks for complications such as surrounding tissue thinning, rippling, and sagging issues over time. 

Hayley Brown, MD
Las Vegas Plastic Surgeon
5.0 out of 5 stars 20 reviews

420cc Implants


If you like the 500 cc sizers than go for it. Otherwise you are setting yourself up for disappointment and the most common post operative compliant of, "I wish I would have gone bigger!"

Darryl J. Blinski, MD
Miami Plastic Surgeon
4.5 out of 5 stars 61 reviews

Breast augmentation; choose the look, not the implant size


Your question comes up very frequently and we hear such concerns; will a 350cc implant be right for me? Or will I need a 420cc implant for a DD cup or will a 450cc be better? As a reviewer, my best advice is to make sure you know what look you want (and yes cup size) and make even more certain that your surgeon knows what the goal is. You will not care if the implant is a 400cc or a 475cc if the look is 'you'. Bring in photos, buy the bra you hope to wear (the 34DD) and fill it out and let your surgeon see it to know what you want. The surgeon should keep your goal clearly in mind as he selects the correct implant. He should also advise you as to a safe and realistic outcome.

Best of luck,


Peter E. Johnson, MD
Chicago Plastic Surgeon
4.0 out of 5 stars 26 reviews

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.