475cc Saline to 600cc HP Gel - Too Big?

AT your less than average height, I would not recommend the 600 cc implant without a discussion of the long term consequences. Without trying to sound too insulting, a very large implant (600 cc is) can make a shorter prson appear more heavy and you will be pressured to remain thin or wear garments that exaggerate your waist and crate an hourglass figure in order to avoid the appearance of a round midsection

Breast implant size is a very individual decision with multiple variables. These include, height and weight, chest size, and pre-existing implants. It sounds like you already have large implants in place and are small framed. It is unclear why you want to change the implants out, but likely you have stretched out and your breasts have thinned and sagged with the large implants. Commonly the thought is just put in a larger implant which it sounds like you have been recommended, though likely you need a breast lift with a size appropriate implant. Consider a second opinion because some decisions will prove costly and irreversible.

Without examining you, it is difficult to comment on what is "too big."  However, 650 cc implants are large and can add considerable weight to your chest.  The effect of the added weight can be a stress on your skin which may lead to stretching over time.  My advice is to discuss your expectations with your surgeon, including the risks and benefits in your specific case.  Good luck.

Every patient and body frame is different, but for your frame, height, and weight, 600 cc implants is farily big.  Too big is in the eyes of the beholder, but 600 cc breast implants would probably be difficult to accomodate in a normal bra long term.

You are also in danger of stretch marks, early breast ptosis/ breast sag, and will probably need a breast lift much sooner than a smaller breast implant size. 

Thank you for your question. It is much better to accurately discuss implant volume and projection with an in office exam and detailed measurements. In order to make an accurate size recommendation, I would need to assess your chest wall and breast mound measurements/characteristics. I use these measurements to help me during the sizing process to guide you to a safe result for your chest wall and just as important, one that meets your end desires.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 during the sizing process. In addition, review of photos and use of rice bags can be very helpful to the patient and surgeon in achieving a safe and happy result. Close intereaction and involvement from your surgeon during this process can help alleviate the anxiety and fears of choosing the right size. I wish you a safe recovery and fantastic result.Dr. Gill