Will 250cc Silicone Moderate Plus Implants Be Too Big?

I don't think you will be too big.  250cc moderate plus, under the muscle might not get you to a C cup however.  "Natural" is not only dependent on the size but also on making a preper pocket for the implant.  I suggest you bring pictures of your desired results to your PS to make sure you areboth on the same page.

At size 34 A each 100 cc’s of implant corresponds to 1 cup size change.  To go to a size C would require 200 cc implants.  I always recommend silicone gel implants placed retro-pectoral since they look and feel more natural, are less likely to ripple and are more stable long term.  In the retro-pectoral position, the profile of the implant is irrelevant since the muscle compresses it.  Unfortunately, you have not provided any photographs but you may also benefit from a simultaneous Mini Ultimate Breast Lift.  This technique only uses a circumareola incision to place the implant, reshape your breast tissue creating upper pole fullness, elevate them higher on the chest wall and more medial to increase your cleavage.  Aligning the areola, breast tissue and implant over the bony prominence of the chest wall gives maximum anterior projection with a minimal size implant.  Breast Augmentation with Mini Ultimate Breast Lift will give you the natural look with the smallest implant possible and least amount of scarring. 

 

Best Wishes,

Gary Horndeski, M.D.

Without photos it is very difficult to suggest a breast implant size. But to achieve a C-cup you, generally, need larger implants. Ultimately, you need to be examined in order to best determine the most appropriate breast implant size for you.