Maximum Cup Size Through Breast Implants?

The rate of complications clearly increase as you go with larger sized implants. In many instances it may be better to stage the operation In the united states, the largest size implants approximate 1200cc. However, your name would seem to indicate that you are in London. It is my understanding that larger implants are avialable in Europe. However, this would go under the title of: "just because you can doesn't mean you should". Schedule a consultation with a credentialed surgeon and review the risks that are associated with larger sized breast implants.

First of all I like to get my patients away from talking about "cup size" because there is a huge variability in what one bra maker's "B" cup might be. One company's "A" cup might equal another's "C" cup, etc.
I think the it mostly depends on your tissues and your measurements. As far as your tissues, have you had children before? If the breasts have previously "expanded" with lactation from pregnancy, there is usually more tissue laxity and it can be easier to accommodate a larger implant than in a patient that has never had children and the tissues are "tighter".
As far as measurements, I think there are a number of scientific measurements that I utilize in the office (something we call biodimensional planning) that helps "guide" a patient to an implant size or range of sizes that best fits their body and chest wall frame. Just like when a tailor measures you for a suit, there are certain numbers that we use make sure the coat is custom fitted to our bodies. In the same way, a breast implant gets bigger in diameter as the size gets larger and using really larger sizes in small patients can lead to many more complications, such as synmastia (implants merging together in the center with no cleavage) and implant malposition such as bottoming out and implants being way to far out on the sides.
Studies have shown many more complications in breast implant sizes over 400 cc. If you naturally wear a 30 B then that tells me you are quite narrow chested and even if you are a natural B cup I think you might be able to get easily 1 full cup size increase, maybe 1 1/2 depending. When you try to do more than that is when you run into problems.
Overstretching your tissues with way too large of an implant can be a bad problem. Some patients may like this in the short term, but over time the overstretching and tension on the tissues causes more issues with implant visibility, wrinkling, and rippling as well as malposition. I do a number of revision breast surgeries and when these patients come back and want a smaller implant, if the breast skin has been overstretched by an initial larger implant, oftentimes a breast lift is necessary which adds additional scars.
Think about it carefully, because the best chance of a successful good result involves careful preoperative planning.
I hope this helps!

Going from a B cup to C or D cup with breast augmentation is certainly possible and is a straightforward procedure. When a patient wishes to be much larger than that, I will always advise them of the toll large implants can take on your breast skin over time. The skin often cannot tolerate the large implants and will stretch over the course of the years, and over time the results may not be as aesthetically pleasing as you would like.
It's always easier to go bigger later, but more difficult to downsize. I would have a very honest discussion with your surgeon about the pros and cons of a modest augmentation versus a very dramatic difference, and as long as you are comfortable with the plan, then you should proceed.
Good luck!

Dr. S