Should I lose weight before or after fat transfer to the breasts? Will my breasts deflate if I lose weight after surgery?

It would be best for your weight to be stable prior to surgery. I would recommend loosing all the weight you want, then consider the surgery. You will need donor fat for the surgery to be successful.

Thank you for your question. Based on your description, you may benefit from fat transfer. Fat is living tissue and, like a farmer planting seeds in a garden, requires even distribution to maximize its survival. This is also, likely, very technique dependent. Fat can be unpredictable with regard to its volume, however, once integrated into the tissues, it has the potential to last a lifetime. Based on the volume available and the parameters of your breast, you may or may not experience significant changes in your final outcome. Brava expansion may be necessary to provide additional volume retention, however, this modality is currently not available as the company is no longer producing the domes.
I would certainly encourage you to be near your ideal body weight for fat transfer and not gain weight as is often suggested. Fat cells are not unlike balloons where a fixed number exist. Gaining weight only serves to increase the volume of the balloons and not their number. This would actually make heavier patients less ideal for transfer as it would leave them with a fewer number of larger balloons rather than a greater number of small ones which would be ideal. I would certainly recommend that you visit with a board certified plastic surgeon who is experienced in all these matters. I hope this helps and have a wonderful day. Dr. Kayser - Detroit