The driver remains in a critical condition in hospital in Grenoble hospital in France with head injuries suffered Sunday morning at the resort of Meribel. "We cannot tell you what the outcome will be yet," the doctors treating him told a news conference Monday morning.
Schumacher's family were at his bedside. He underwent surgery on arrival at the University Hospital in Grenoble.
He remains in a coma and the medical team treating him said that they were working "hour by hour".
"All we can do is wait," they added.
Schumacher is the most successful Formula One driver of all time with a record 91 victories among his achievements. He won his titles with Benetton and Ferrari.
The German, who lives in Switzerland with his wife and two children, left the sport in 2012 after a three-year comeback with Mercedes following an earlier retirement from Ferrari in 2006-end.