3 weeks post op Brazilian Butt Lift with hip fat transfer. When can I start sitting and sleeping on my back? (photos)

Great question!  I always recommend my patients get some type of BBL pillow that allows you to sit by placing all the pressure on the thighs and not the buttock.  With this pillow you can begin sitting right after surgery.  I recommend my patients to use this pillow anytime they sit for the first 2 weeks.  Also  to lay on the front or side to side for the first 2 week, then they can start laying on their backs.  After the first 2 weeks, my patients can begin sitting without the pillow for short periods of time 5-10 min, then to get up and walk a bit.  After one month all the fat that will survive will have done so and patients may sit and lay however they desire.Best of luck and hope this information helps!- Roger Tsai   @DrRogerTsai

After a Brazilian Butt Lift (BBL) with hip fat transfer, the timing for sitting and sleeping on your back varies, but general guidelines suggest avoiding direct pressure on the buttocks for at least the first 2-4 weeks. At 3 weeks post-op, it's generally considered safe to begin sitting for short periods, especially if you're using a BBL pillow to avoid direct pressure on the buttocks. You can also start sleeping on your back, but it's important to continue using pillows or other methods to keep pressure off the buttocks during sleep.
However, every surgeon has their own specific post-operative recommendations, so it's important to follow your surgeon's personalized advice. The first 6 weeks are typically the most important in preserving the transferred fat, so minimizing pressure during this time will improve the likelihood of fat survival and help achieve the best long-term results.
Krishna Vyas, MD, PhD, MHSHarvard, Hopkins, & Mayo Clinic Trained Aesthetic Plastic SurgeonNew York, New York

This is a great question and you will get a lot of different answers depending on your plastic surgeon.  The idea behind not sitting or sleeping on your butt is to relieve as much pressure as possible on the butt to protect the fat that was transferred to your butt. 
The idea behind decreasing the pressure on the butt is that it allows new blood vessels to grow into your transferred fat and thus letting it survive or “take” for years to come.  Pressure makes it difficult for the blood flow to get to the fat and decreases how much fat is going to survive. 

The exact amount of time that is needed to protect your fat is up for debate.  There are no good studies currently available to help guide plastic surgeons as to the exact amount of time that they should have their patients stay off their butt.  Typical ranges are from 2 weeks to two months.  In our practice we have patients stay off the butt for six weeks, this includes sitting and sleeping on their back.  When I initially started practice, I only had patients off their butt for two weeks, however I found that in my personal practice patients that stayed off the butt longer were retaining more fat.  Thus, we made the recommendation change in our practice to keep patients off their buttock for 6 weeks.   

The more patients can stay off the butt the more fat they will be able to retain.  No question the first couple of weeks are the most important.  If you have questions please discuss your specific instructions for your Brazilian Butt Lift with your Board-Certified Plastic Surgeon.