How long do you know if fat cells in your butt have died?

Hi, thank you for sharing your question. The obvious way to know if fat has survived or not is the shape of your butt and the symmetry between the buttocks. The best way to know is obtaining an MRI which can evaluate the fat to see if it is healthy or not.

Dear GeezLouise0,
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. In case of fat necrosis, you will see subtle changes over time.
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

Usually by 6 weeks if you see changes still occurring then your fat cells are still trying to "live". But if at 6 weeks you are same size as the previous weeks you are healed.

Hi and welcome to our forum!Following a BBL, the fat transferred to the buttocks initially survives by imbibing fluid from surrounding viable tissues. It will later vascularize. If certain cells do not have adequate circulation, these fat cells will die and be resorbed. Following BBL, you will typically lose 35-40% of the injected fat. This will be apparent by a gradual loss of volume over a period of 6 weeks or so. Visit a board certified plastic surgeon for evaluation and discussion.Best wishes...