Sharon Osbourne has revealed doctors have no idea why she "passed out for 20 minutes" in December.
The former X Factor judge, 70, fell ill while filming her son Jack Osbourne's show, Jack Osbourne's Night of Terror, in Santa Paula, California in mid-December and was subsequently taken to hospital.
Jack, 37, later confirmed her release from the facility and she told her Instagram followers she was "back home and doing great".
The reality TV star made her first appearance on her TalkTV show since the incident on Tuesday and told her The Talk co-hosts that she was feeling "very good" after a "quiet" Christmas and was happy to be back in the U.K.
Her co-host JJ Anisiobi asked about her medical emergency and the presenter admitted she "wished" she had an explanation for her health scare, but the doctors were unable to find the exact cause of her collapse.
"It was a weird thing", she continued. "I was doing some filming and suddenly, they tell me that I (passed out) for 20 minutes and I was in hospital. I went to one and then went to another. I did every test over two days and nobody knows why I fell ill."
"So they still don’t know why you passed out?" asked JJ, to which Sharon simply stated, "No."