Leah Cambridge, 29, is said to have died after undergoing a “Brazilian butt lift” at a clinic that boasts celebrity clientele.
The procedure, which reshapes the buttocks by transferring fat from areas including the stomach and back, has become an increasingly popular technique for achieving an hourglass figure.
Ms Cambridge, a beautician from the city, is reported to have travelled to a clinic in the city of Izmir for the £3,000 operation.
Her partner, Scott Franks, 31, said he had been left a “broken man” and warned others considering going under the knife to think about the risks.
“People need to be aware of situations that can happen with this treatment,” he told The Sun.
“We are still waiting for answers and are also trying to get a flight to bring Leah home.”
The huge popularity of curvier celebrities including Kim Kardashian, Kylie Jenner and Nicki Minaj has seen some women go to extreme lengths to emulate their hourglass figures.
Advocates of the Brazilian butt lift, or BBL, say it achieves results quickly and recovery is usually fast.
However, experts have warned it carries a risk of serious complications.
Another British woman, Joy Williams, died following “buttock augmentation surgery” in Bangkok, Thailand, in October 2014.
Her wounds became infected, and the 24-year-old, from London, later died under anaesthetic.
In 2011, 20-year-old Claudia Aderotimi, from Hackney, east London, died after having a “buttock-enhancement” procedure at an American hotel.