I'm 4 weeks post op from my Brazilian Butt Lift and I was wondering if my butt can shrink or expand more?

After the first week from the BBL, usually you will see the swelling to go down and the volume on the buttock will be less, at 4 weeks after the surgery, you cannot expect that the buttocks will look bigger just smaller, because by that time more swelling is going away and also the fat cells that did not take will be gone by that time, usually between 3 to 4 weeks after the surgery you can see the final size of the buttocks. If you gain weight, you may see an increase in the size of the buttocks, but also in other areas of your body, it is not a good idea to gain too much weight after the surgery so your body looks still in proportion.

After a fat transfer procedure to the buttock, it will take at least three months for you to see your final result to allow for shrinkage of the fat cells. You may lose anywhere from 30-50% of the fat cell volume during this time.Best wishes,Dr.Bruno

Hello dear!!
Thanks for the question and provided information as well.
You are still early on the healing process, it can take up to six months to see your final results, so please be patient​. After a BBL, only about 70% of the transferred fat cells will survive, so you can expect a reduction in your buttocks. If you have any concerns, I suggest you follow up close with your plastic surgeon.
Good luck :)