LONDON — A UK plastic surgery organization has warned members not to perform Brazilian butt lifts, after a second British woman died from the procedure this year.

The surgery is immensely popular, despite having the highest death rate of all cosmetic procedures, according to a statement from the British Association of Aesthetic Plastic Surgeons. But what exactly makes it so dangerous?

Brazilian butt lifts or BBL involve taking excess fat from other parts of the body, such as the stomach and back, and injecting it into the glutes to enhance them.

The procedure carries a large risk of fat cells being mistakenly injected into large veins and going into the bloodstream. This can lead to a fat embolism, which can block blood vessels in the heart, lungs, or brain and cause death.

Other complications that can stem from BBL include bacterial infections, wound ruptures, and necrosis, among others.

Experts say many patients who have suffered botched surgeries had the procedure done abroad where it's cheaper.