BRITAIN'S most successful female jockey has quit the saddle after losing an ongoing battle with her weight.

Alex Greaves, 36, rode more than 300 winners in her 15 years as a professional and made history as the first woman to ride a Group One winner. She was also the first female to compete in the Epsom Derby and the 1,000 Guineas.

She is married to trainer David Nicholls and the couple have built up a successful training business at Sessay, near Thirsk, North Yorkshire.

She has battled with the scales for years and recently has only been comfortable riding at nine stones.

She told the Racing Post: "I'll miss it like hell, but I know at the bottom of my heart it's the right decision.

"Most girl riders get on because they are light, but I've always struggled with my weight and it doesn't get any easier.

"Being a girl in this game, you have to work twice as hard to prove yourself and, after 15 years of pushing hard all of the way, I know it's the right decision."

Greaves started out as an amateur with David Barron and rode her first winner at Southwell in 1989. She landed her first big success aboard Amenable in the 1991 Lincoln, before becoming the first female apprentice in Britain to ride out her claim.

"I'm very proud of my record and I've had a real ball," she said. "I've ridden all over the world, including Japan, Hong Kong, France, Ireland and Barbados."

Greaves made history as the first female jockey to ride a Group One winner when dead-heating on Ya Malak in the 1997 Nunthorpe Stakes at York.

She also partnered sprinter Zuhair to three of his four successive wins in Goodwood's Charlton Stakes, a race now named in the horse's honour.