Breast augmentation with fat grafting: how long do the results last, and how much fat is retained?

Nobody can predict how much fat can be retained. The newer fat grafting techniques have greatly improved the "take." Also, adding your PRP (platelet rich plasma) to the fat graft will improve the take.
However, an augmentation mammoplasty with submuscular prostheses will give you the desired 1.5 cup enlargement. I would use a moderate plus or high profile prosthesis to give the anterior projection and limit the width. Intraop, the size of the prosthesis can be determined to be ideal, so as not to create the breast that is too large for your desire. 

It is important to remember that breast augmentation by fat transfer is actually two operations.  The first is harvest of the fat from the donor site(s).  Typically, we will harvest the fat from the abdomen, flanks, or inner or outer thighs, and often some combination of these areas.  In order to obtain enough fat to transfer to the breast, we will typically need 150cc-300cc to place in each breast over a breast implant, and up to 500cc for each breast, if no implant is being placed.  In obtaining such volumes of fat for transfer to the breasts, enough fat is usually removed from the donor sites to result in a noticeable improvement in the contour of the liposuctioned areas.  We then purify and concentrate the fat for injection into the breast.The second part of the surgery is the transfer of the fat to the breast.  Although the volume of the breast can be improved with fat transfer to the breast alone, we find that combining fat transfer with placement of a breast implant allows the surgeon more control over shaping the breast intraoperatively,  as well as insuring that the increase in breast volume and improvement in breast shape and symmetry, lasts longer term.  In general, about 50-60% of the fat injected into the breast parenchyma survives.  Once the surviving transferred fat is integrated into the breast tissue, it should remain there for the lifetime of the patient.  Because we know that not all of the transferred fat survives, we typically transfer a bit of extra fat to each breast to anticipate this loss.  In about 10% of cases, we will perform secondary touch-up fat transfer six months after the initial procedure.  Most of our patients who undergo fat transfer to the breast are extremely pleased, not just with the increase in size, and the improvement in shape and symmetry, but also with the very natural appearance of their breasts.

This is a permanent procedure but graft survival rates vary widely.  Efficiently transferring the fat from the donor site to the breast will improve graft survival.  A fat grafting liposuction system improves efficiency.