The actress and singer is one of 12 celebrities who signed up for the new series.
But getting her to say yes proved a lot of work for show bosses, Donna has admitted.
"I was terrified about doing it, so I took quite a long time to agree," she said this week. “I thought I’d probably die doing the show as it was that dangerous.
"But I’m so glad I made the right decision.
“I’m enjoying the training so much more than I thought I would and I’ve now realised I’m not actually going to die.”
As well as being reassured she won't die, Donna has also had some more good news from the Dancing On Ice's coaches.
5ft 9 Donna has been ruled out of doing the show's famously risky 'headbanger' move.
"I've been ruled out of doing the Headbanger, because I'm too tall!" she said.
Speaking from training, Donna went on to reveal the changes her body had seen after rehearsals.
"For purely superficial reasons, I’m very happy my bottom is going in the right direction," she said. “I might start drawing little markers on the wall to see how high it gets. I’d rather do something where you’re having an experience and you notice your body changing. I hate the gym.
“I think it’s really important for the girls and women to be strong, and I can feel my body getting stronger.”
Celebrities joining Donna on the Dancing On Ice 2018 cast include Coronation Street actress Brooke Vincent, Bucks Fizz singer Cheryl Baker, X Factor singer Jake Quickenden, Rugby hunk Max Evans, and ITV Weatherman Alex Beresford.
Meanwhile, a new look judging panel is made up of Jason Gardiner, Diversity dancer Ashley Banjo and skating duo Jayne Torvill and Christopher Dean, who were coaches on the original series.
Dancing On Ice continues Sunday nights on ITV.