Michael Schumacher, the most decorated Formula One driver in history, remains in stable but not critical condition more than two weeks after he was placed in a coma in a French hospital following a skiing accident.

Schumacher’s physicians have not updated the retired driver’s condition to the public for more than one week. German media is speculating he may not emerge from the coma.

“The sooner an artificial coma ends, the faster return usually normal body functions such as breathing,” Heinz Peter Moecke, director of the Institute for Emergency Medicine, Asklepios Kliniken in Hamburg told the German newspaper Bild.

Moecke said patients are usually kept in a coma for a few days or at most one or two weeks because they could have problems such as swelling in the brain or liver damage due to the medication.

The newspaper also reports there are currently no plans to awaken Schumacher from the coma because the injuries are too severe.

Andreas Zieger, a neurosurgeon in Oldenburg, Germany, warns against speculation.

“Brain injuries are among the most complicated injuries that can happen to the human body,” he told the German newspaper Focus. “Therefore individual predictions about the course and potential complications cannot in all cases (be) reliable.”

Video from a camera on Schumacher’s helmet showed he was skiing off a groomed trail when he lost his balance and crashed at Meribel where he owns a chalet. Schumacher suffered injuries to his head as a result of the crash and his helmet split when he hit a rock.

Schumacher, who turned age 45 last week, had 91 total victories and 155 podium finishes in his 19-year career.