Partially removed fat graft
Our current thinking is that once a fat graft has incorporated (blood supply has grown into it), it does not grow unless the patient gains weight. Then, the fat graft seems to behave like tissue where the graft was harvested. For example, if the graft was harvested from the abdomen, it behaves as abdominal fat.
So in most cases, a fat graft should not "increase" unless the patient gains weight.
Fat grafting and steroid injections
The injection of steroids into the skin is a significant event at the cellular level. After such an injection, your skin will be probably changed. The skin will be thinner and will have more difficulty healing. When a steroid is injected into a fat grafted area, the fat will shrink and contract. This may be the effect that he wants if steroid is injected into an area that may have a little too much volume.
Will fat transfer (grafts or injection) grow or regenerate after transfer
Generally the fat grafts will not regenerate. However, they can grow if you gain weight. Therefore it is important to remain at a stable weight following fat transfer.