The 61-year-old head judge said viewers had helped her discover “concerning” symptoms in her body.
After seeking medical advice, Shirley said that doctors had discovered her hormone levels are “not right” and she needs some scans.
“All in all a little concerning for my doctor,” she said, adding that she had made a hospital appointment.
She wrote on Instagram that her doctor was “making an appointment to check certain odd things happening in my body”.
“To each and every one of you who started me on this road thank you so much,” she began. “I’ll keep you all updated. Remember health is wealth so I’ll be on top of these issues for the time being. With gratitude to you all.”
In an accompanying video message, the former ballroom champion – who had surgery to have breast implants removed in 2019 – said tests had shown her testosterone levels to be “ultra-high”, her oestrogen levels “extremely low”, and that she needs scans on her adrenal glands and ovaries.
Olympian Adam Peaty, who is competing in the current series, added: “Sending all my love and positive energy.”