Britain’s leading female jockey, Hayley Turner, has been stood down from race-riding for a year.

Hayley, 26, was knocked unconscious in an accident on Newmarket’s gallops on 3 March.

Today she met the British Horseracing Authority’s chief medical adviser, Dr Michael Turner, to discuss when she could return to the saddle.

Dr Turner said: “Having carefully studied the results of recent tests and consulted expert opinion, I was unable to recommend that her licence be renewed until 12 months from the date of the accident.

Hayley has recovered well from her injuries but you cannot take any chances in cases like this.”

In a statement, Hayley said: “I am absolutely devastated. I know I am very lucky to be in one piece and I will be back riding, but a year is long time.”

Hayley Turner became the first female jockey to ride 100 winners in a calendar year in 2008, and was joint-champion apprentice in 2005.

She regularly rides for H&H racing columnist Michael Bell, and is “the face of the Derby” for 2009.