I am 5'7", 180 lbs & athletic build. Will I look natural with 550cc/600cc? (photos)

Based on your photographs you will need projection, surface area, and volume to correct the breast shape.  It will require a large implant.  Your goal pictures will be difficult to achieve because those patients did not have sagging before surgery.  If you are looking at the size of the goal pictures, they are large.  So the recommendations are more realistic, now knowing this information.  However, the best way for you to ease your fears about going large is to try on sizers.  If the surgeon you love doesn't offer this option, then you have to figure a way to make sizers of your own.  Instead of rice, try freeze dried mashed potato (uncooked), measured in cc using your measuring cup, and placed in knee high panty hose.  Make sets of sizers and put them in your bras, or bathing suits.  Try on 600 cc.  The sizers will look approximately 40 cc larger than the implants, so if 600 cc is slightly large but doesn't really bother you, it will probably be good.  Looking at pictures of other patients with 600 cc is the worst way to see how it is going to look on you.  Don't let that scare you.  Smaller implants are not going to correct your shape.

The photos provided are not full views - it is unclear if there is a difference in size or nipple position, or to assess the position of your nipple on your breasts.  When looking at photos of other people who had BA I would recommend comparing pictures of people who had a similar appearance as you before the surgery.  This will give a better idea if you might achieve he same result after surgery.

You should seek out a board certified plastic surgeon that offers 3D imaging and simulation, in office gel sizers, custom rize sizers and bio-dimensional analysis. Our office uses all of these techniques on all of our patients to achieve a 99.8% success rate with size satisfaction.

Depends on what you call natural. Most "athletically" built women don't have don't have such large breasts. 

Hello, you can ask ten people and get ten different opinions about what is natural to them. In general, based on your Ht and wt, a 550/600 implant is not unheard of. You final size also depends on how much breast tissue you have right now. I would recommend trying sizers in the office to help you visualize how your are going to look. Ask your PS if he as a breast sizing system with shaped sizers that can conform to your breast...these can be helpful when trying to decide on your desirable size. In addition to this, there are 3-d computer imaging systems that can also give you a good idea of what you may look like. Good Luck.

Judging by the photos I think you can handle that size without looking disproportionate. You may need a breast lift as well.  

It is difficult to tell you what would be best for you without an appropriate exam in person.  Best of luck with your decision to move forward.

The best results occur when you are sized and fitted in the operating room.  No matter what modality is used to "preview" your look before surgery the ultimate selection is in the OR.  Pre-op techniques to size you may be of modest benefit but all of them have some prediction flaws.  Especially viewing various size implants on other people.  Everyone is different.The best technique is for you to portray to your PS what type of results you want.  You have done this by providing photographs of the desired goals.  Then your PS should then do his/her very best to achieve those results.  Factors that influence the results are:1. your anatomy2. the volume and quality of existing breast tissue3. how droopy your breasts are and how large the skin envelope is4. your expectation for size and shape.You seem to have slight asymmetry although the photograph angle is poor.  And you also have slight ptosis (sagging).  To get the best correction for you I would generally recommend areolar approach with a shaped implant that is high or ultra profile.  I feel that can provide you with the best "lift effect", shape and projection.  The size of implant to be determined in the OR based on the results you want.I hope this helps

Thank you for the question and pictures.  Unfortunately, online consultants will not be able to provide you with specific enough advice (regarding specific breast implant size/profile) to be truly helpful. Given that your surgery is coming up soon, I would suggest that you spend more time with your plastic surgeon communicating your goals carefully.
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. In bra sizers can be useful communication tools also. I have found that the use of words such as  “natural” or "C or D cup" etc 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.  The use of computer imaging may be very helpful during the communication process.
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, and the attached link (dedicated to breast augmentation surgery concerns), helps. Best wishes for an outcome that you will be very pleased with.