Is 375cc silicone under the muscle too big? I’m 5’5, 120lbs, athletic. (Photos)

Hello and thank you for your question. Honestly, a formal in-person evaluation would be needed to determine the best treatment. There are several reasons for this:
1) Bra sizes vary based on the clothing store (for example, Victoria's Secret tends to upsize everyone by a whole cup size)
2) Most women do not wear the proper exact fitting bra size for their bodies
3) The exact volume (in cc) needed to change cup size is different for different body types (e.g. 32A to 32D requires a different implant size than 38A to 38D)
4) Be careful NOT to fall into the trap most women do- they see a certain implant size (e.g. 285 cc) or perhaps their friend had a certain size, and they want or request this or another size based on that. Everyone's body is different- 285 cc implants on your friend might look VERY different than they would on you. Be very careful not to make this mistake, because the goal is to find the right size and shape for YOU- for your particular body and your breasts.

Because of those multiple factors, and because it is KEY to fully evaluate your breasts in person to make a full set of precise measurements to select the proper implant for you (incorporating factors like amount of breast tissue, implant type, base width, projection, etc), answering your question really would need a formal personalized consultation- to say anything before that would simply be guessing, which would be both unfair and unhelpful to you. Also, just FYI, each surgeon's measurements are slightly different, so numbers, experience, and overall aesthetic from one surgeon aren't necessarily the same as those from another surgeon!

Your breasts are such a KEY area of your body and your femininity- therefore, you should ONLY trust an experienced aesthetic plastic surgeon. As such an expert, I have had extensive training and experience with complex aesthetic surgeries under a multiple world-renowned experts in the field. I’d recommend for you to setup a formal consultation with me (or another plastic surgeon who is extremely comfortable with aesthetic plastic surgery procedures) for a formal consultation to thoroughly discuss your surgical goals, undergo a formal examination, evaluate all your options (surgical and nonsurgical), and decide on the best procedure(s) and type of anesthesia for your specific case.

I'm located right here in Los Angeles. I hope this helps!

Dr. Donald Groves
Aesthetic Plastic Surgeon

Hello,
The dotted line drawn on your chest represents a very large and unpredictable drop in your inframammary fold, and would likely lead to any or all of these undesirable results: drop out, double bubble, and severe rippling. You simply are not a candidate for an implant anywhere near as large. Go visit a few ABPS certified/ASAPS member surgeons who specialize in breast surgery and respect bio-dimensional analysis. Best of luck!

Sizing is a very personalized process and it is very difficult to give any advice online without an accurate exam with measurements.  Looking at friends and others online to determine if the 375 is right for you will likely confuse things more as 375 cc on one person as you mentioned can be a C cup and on another DD.  There is a lot that we do at my practice for determining what size implant we will be placing, its a process.I would recommend you discuss this further with your plastic surgeon to make certain you are getting what you are envisioning.Hope that helps.

can be accomplished with the use of sizers in unlined bras.  Whatever sizer is chosen as the one you want to replicate, add 10% to that volume to get your implant volume or you will look smaller than what you thought you would be.  So a 325 cc sizer would be just a little smaller than what you would look like with a 375 cc implant.  You could try to make a homemade sizer with rice using 1.5 cups of rice that would give you a sizer of 360 cc's and if you feel its too large, the 375 cc implant should be fine.  If the 360 cc sizer is too small, you may want to consider increasing your implant size a bit.  As for profile, your implant should be close to the natural width of your breasts and if you have a big gap between your mounds, you may want an even wider implant if your surgeon is not handicapped by the concept of not releasing your medial tissue.  You want the widest base implant that will fit on your chest without creating symmastia.  Best wishes with getting what you are hoping for.

 I think that you have a good plan already: more communication.
It is definitely worth spending more time (prior to the date of surgery) with your plastic surgeon to discuss further.  As you know, it will be important for many reasons, that you feel comfortable that you and your plastic surgeon are on the "same page" prior to proceeding.
One question that might be helpful for you to consider: would you be more disappointed if you are slightly too big or slightly too small after the breast augmentation procedure?
Ultimately, careful communication of your goals (in my practice I prefer the use of goal pictures, direct examination/communication in front of a full-length mirror, in bra sizers, and computer imaging) as well as careful measurements (dimensional planning) will be critical.
Generally speaking, the best online advice I can give to ladies who are considering breast augmentation surgery (regarding breast implant size/profile selection) is:
1. Concentrate on choosing your plastic surgeon carefully. Concentrate on appropriate training, certification, and the ability of the plastic surgeon to achieve the results you are looking for. Ask to see lots of examples of his/her work.
2. Have a full discussion and communication regarding your desired goals with your plastic surgeon. This communication will be critical in determining breast implant size/type/profile will most likely help achieve your goals. 
In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. For example, I have found that the use of words such as “natural” or "C or D cup” or "too big" etc means different things to different people and therefore prove unhelpful.
Also, as you know, cup size varies depending on him who makes the bra; therefore, discussing desired cup size may also be inaccurate. Again, the use of computer imaging has been very helpful during the communication process, in our practice.
3. Once you feel you have communicated your goals clearly, allow your plastic surgeon to use his/her years of experience/judgment to choose the breast implant size/profile that will best meet your goals. Again, in my practice, this decision is usually made during surgery, after the use of temporary intraoperative sizers.
I hope this helps. Best wishes for an outcome that you will be very pleased with. 

Whether your 375 cc implant is too large or not for you is based on your nipple to crease distance; this should match the radius of your implant; the line drawn under your breast is very concerning as it hints that your inframammary crease is going to be lowered; this is the ultimate NO NO as the inframammary crease should not be violated; once it is released, you will have a lifetime of bottoming out and risk a double bubble appearance. Please make a consultation with a breast specialist to appreciate the nuances of breast augmentation surgery.

TOO is a value judgement-> too big in whose eyes - 375 should make you a full “c” if you wear a 34 bra.  If you have concerns though go put implants in a bra till you see the volume on your chest that you likeDr Corbin

It's of course more accurate to make a recommendation based on a face-to-face physical examination and consultation but I'm concerned by both the size of the implant and the degree of lowering of your inframammary crease that seems to be the proposed plan on your photographs. I personally think that this increases the risk of a double bubble deformity or a dropout due to excessive lowering of the IMC. I also would recommend against the use of a high profile implant since this tends to create a less natural appearance despite its lower diameter.Perhaps you should seek a second opinion or second consultation with your treating plastic surgeon. I find it best in my practice to have patients review photographs with me of patients whose results they like and then ask them to allow me to use my best judgment in selecting the implant during the surgical procedure and not before. This allows me to make adjustments based on the appearance of a test implant called a sizer to get the best aesthetic combination of contour, shape and size for them.Discuss your goals carefully with your plastic surgeon and best wishes for a good result. Enjoy the video link below for further discussion of size choices.Jon A. Perlman, M.D., FACSDiplomate, American Board of Plastic SurgeryAssociate Clinical Professor of Plastic Surgery Geffen/UCLA Medical CenterExtreme Makeover, ABC TV plastic surgeonBeverly Hills, Ca.