What size do you think I might be after 800cc silicone sub muscular implants?

Thanks for your question. As the other doctors have stated you will not fit in any traditional bra. Once your implants are placed and the swelling subsides you will have to be fitted. I'm hopeful the surgeon you chose explained the risk of asymmetry, implant malposition and almost certain need for additional surgery. Best of Luck!

If you tried on the sizers and like the size then that is all that is important.  You will need to try bras on afterwards to see what fits you best.

 Thank you for the question but online consultants will not be of much help to you. You may however find the attached link, dedicated to "extra large" breast augmentation surgery concerns, helpful to you as you learn more. Best wishes.

There isn't enough information to answer your question, but you will definetly be BIG!  You will certainly be atleast a DD, and likely bigger.  Make sure that is what you really want before undergoing the procedure.  Seek out a few consultations from a board-certified Plastic Surgeon before making a final decision.  All the Best.

Unfortunately no one can adequately answer that question on this or any other website site other than saying that you will be very large.There are no manufacturers' standards for cup sizing in the
bra industry. The cups of a 38 D or DD and a 40 D or DD are significantly different. Cup
size varies from manufacturer to manufacturer and even within styles from any
particular manufacturer. Nor is there a direct correlation between implant
shape or size and cup size.

Keep in mind that following the advice from a surgeon on this or
any other website who proposes to tell you exactly what to do without examining
you, physically feeling the tissue, assessing your desired outcome, taking a
full medical history, and discussing the pros and cons of each operative
procedure would not be in your best interest. I would suggest that your plastic
surgeon be certified by the American Board of Plastic Surgery and ideally a
member of the American Society for Aesthetic Plastic Surgery (ASAPS) that you
trust and are comfortable with. You should discuss your concerns with that
surgeon in person.

Robert Singer, MD FACS

La Jolla, California