What’s the likelihood of asymmetric breasts after Breast Fat Transfer and fat absorption?

Fat transfer requires carefully liposuctioning fat, processing it, and injecting it. The injection part essentially needs to be drop by drop. If too much fat is injected in any one spot, the centre of the clump of fat will not be near enough to healthy vascularized cells and will not survive. It is important to have a surgeon that has a special interest in fat transfer; careless injection can lead to large cysts. Even when great care is used cysts are still possible, but much less likely.

As far as asymmetric retention, it would be unlikely that all the fat on one side lives and the fat on the other does not. The amount that is maintained is essentially the same on both.

Dear wanderbust,
fat viability depends a lot of surgeon technique. The fat has to be placed back into the buttocks as soon as possible so that it has a greater chance of survival. It has to be placed carefully so that not too much fat is placed in only one area. If you are considering a surgery, I would suggest you to consult a board-certified plastic surgeon. Only after a thorough examination you will get more information and recommendations.
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

The volume of fat transferred is not in multiple liters. The area to receive fat can only accept so much fat at one time. However, the transfer can be repeated after a few months if you still have donor fat and want more volume. With a careful transfer, your breast should be fairly even if they were even prior to transfer.