Connie Fisher has been forced to pull out of a stage production of The Sound Of Music, saying she no longer has the vocal range necessary for the role of Maria.
The 28-year-old, who shot to stardom in the BBC talent show How Do You Solve A Problem Like Maria?, said her voice had undergone a radical change as a result of a throat condition.
She was expected to play Maria in Cardiff, Manchester, Newcastle and Wimbledon until the end of October in a touring production.
Connie said: "After many months of battling with a throat condition, known as congenital sulcus vocalis, my vocal range has altered dramatically and it is with much regret that I have to withdraw from The Sound Of Music as I no longer have the range to sing the part of Maria.
"My journey with this amazing show has been such a magical one and I am devastated that I am not able to close the tour."
The star, who has previously appeared in the tour and took the lead role on stage at the London Palladium, said: "I have loved every minute of working with Andrew Lloyd Webber, (producer) David Ian and the cast and crew of The Sound Of Music and I am only sorry that I am not able to be with them until the last performance."
In 2009, Connie had to call off a 14-date Secret Love UK tour to have immediate surgery on her vocal cords. Specialists in the US advised her to act after diagnosing congenital fusion anomalies.
The former call centre worker will be replaced by Verity Rushworth as Maria opposite Jason Donovan as Captain Von Trapp at the Wales Millennium Centre, when the production opens there later this month.
Fisher's spokeswoman later confirmed that she would never be able to play the famous role again as her voice had changed permanently, but she would be concentrating on other work.