Soul II Soul star Melissa Bell, 48, is battling severe kidney failure and spends eight hours a day on dialysis, The Mirror reports.
She is on the transplant list but has a rare blood type. She could die without a new organ but says it would be "wicked and selfish" to accept her daughter's kidney.
Burke said: "I've tried three or four times. But mum made the choice because the doctors said it could mean I wouldn't be able to conceive.
"She didn't want to restrict me. But I was willing to adopt anyway."
Bell's ill health came to light when Burke was competing on The X Factor in 2008, with Mohamed Al Fayed apparently stepping in to install a dialysis machine at her home and fly over his personal doctor.
Listen to Burke's cover of James Bond theme 'Live and Let Die' below:
