A decade ago, a BBL (Brazilian Butt Lift) was a relatively rare occurrence, but in her piece for The Guardian, Sophie Elmhirst discovers that since 2015 the number of butt lifts performed globally has grown by a whopping 77.7%. Kim Kardashian can take a big chunk of the credit for this, as the proud owner of the most famous bottom in the world, “a bottom so scrutinized, so emulated, so monetized, that it no longer feels like a body part, but its own high-concept venture, its own startup turned major IPO.” However, no one knows how long the fashion for a bottom that resembles “a bauble wrapped in skin” will last, or what will happen when it ends. While it remains in vogue, there are many women willing to run the gauntlet of having fat strategically molded into their rear ends — and some have paid for it with their life.

A patient has to wait weeks before they know what their bottom will ultimately look like. The fat takes time to settle, and Glancey has to remind her patients that at best, only about 50% of the fat “takes”. The rest is absorbed by the body and ejected through the lymphatic system. To optimise the amount of fat that survives in the body requires a surgeon’s skill. Glancey compares it to creating a garden: you can’t put plants too close together, they need space to thrive. “When I say this to patients, they just say put more in,” she said. “And I say, well, it doesn’t work like that.” Glancey sticks to the UK guidelines and limits how much she will insert – 300cc per buttock, a little less than a can of Coke. She tells her patients to complete the BBL over more than one operation, adding a little at a time.

In Turkey, the most popular destination for cosmetic surgery patients travelling abroad in Europe – and the third most popular in the world, after Thailand and Mexico – the limits are less conservative. Some surgeons openly advertise on social media that they will insert more than 1,000cc into a patient’s buttocks. Glancey says that she regularly sees patients who have returned from Turkey unhappy with the results, often because a significant quantity of fat has died and left them lopsided or misshapen.

The risk involved in performing a BBL is not only about the quantity of fat, but how it is inserted. (Also, whether it is fat being inserted at all: a number of recent deaths associated with buttock augmentation occurred because the patient was being injected with silicone.) During the operation, the danger occurs at a very precise moment: the insertion of the cannula into the buttock. As it goes under the skin, the cannula has to remain above the gluteal muscle. If it goes below, and fat enters the bloodstream, fat droplets can then coalesce, travel through the blood and cause a pulmonary embolism, a blood clot in the lungs – the cause of death in the case of the British woman, Leah Cambridge, who had a BBL at a private clinic in Izmir in 2018.