BBL and ultrasound: how fat transfer to the buttocks became safer

The Brazilian Butt Lift, or BBL, is not strictly a lift: it augments the buttocks using your own fat obtained through liposuction. It is one of the world's most popular procedures and one that has changed significantly in recent years.

The 2018 warning

In January 2018, a task force formed by several international plastic surgery societies issued a safety advisory: fat transfer to the buttocks had the highest mortality rate of any cosmetic procedure, at around 1 in 3,000 patients. The concern was so serious that some places considered banning it.

What the investigation found

In reviewing these cases, surgeons found a common cause: fat had been placed inside the gluteal muscle. Large veins run through this muscle, and fat can enter them directly through the cannula or when pressure pushes it between muscle fibers.

The conclusion of the international consensus was clear: the procedure can be done safely provided the fat is placed only above the muscle, in the subcutaneous tissue.

What changed

After surgeons adopted this rule, the mortality rate fell dramatically. Later data put it at around 1 in 15,000, comparable to other body-contouring procedures.

The challenge: knowing where the cannula is

Fat transfer was traditionally performed without direct visualization: the surgeon could not see the plane where the fat was being placed. Portable ultrasound changed that. We can now see each injection in real time and confirm that it remains above the muscle. It also helps avoid placing fat too superficially, where it can cause irregularities.

Ultrasound guidance is so important that Florida, where this procedure is especially common, has required it by law since 2023.

How I do it

In my practice, fat is always placed above the gluteal muscle, under ultrasound guidance, in a hospital. This is more than a technical detail: it is the difference between cosmetic surgery and unnecessary risk.

If you are considering buttock augmentation with fat, ask your surgeon two questions: in which tissue plane will the fat be placed, and will ultrasound be used to verify it? A board-certified plastic surgeon should answer both without hesitation.