Olympic gold medallist Victoria Pendleton has abandoned her Everest expedition after suffering from oxygen deprivation.

The track cyclist-turned-jockey had set out for the summit with TV adventurer Ben Fogle.

Pendleton, 37, had reached the mountain's Second Camp, 21,000ft above sea level, after spending many weeks preparing for the final climb.

Olympic gold medallist Victoria Pendleton has abandoned her Everest expedition with TV adventurer Ben Fogle (pictured at base camp together)

Pendleton, 37, had reached the mountain's Second Camp, 21,000ft above sea level, after spending many weeks preparing for the final climb

But she started suffering the effects of hypoxia – which can be fatal – and needed to be given oxygen. She was advised by her doctor to end her climb raising money for the British Red Cross, according to The Daily Telegraph.

'I am incredibly disappointed not to complete the challenge,' she said while at the Base Camp of the world's tallest mountain.

'I am extremely grateful for this opportunity to have experienced one of the most impressive, imposing and challenging environments on the planet.

'The Himalayas are a magical place I feel honoured to have visited.' Fogle, 44, will continue the expedition without her.

But she started suffering the effects of hypoxia – which can be fatal – and needed to be given oxygen. She was advised by her doctor to end her climb

Dubbed 'Queen Victoria', Pendleton, from Stotfold in Bedfordshire, admitted in December that she was taking part in the challenge because she was 'probably having a midlife crisis'

Mountaineers are recommended to carry oxygen bottles on high-altitude climbs to prevent hypoxia.

An expedition spokesman said: 'No individual can predict exactly how their body will respond to the effects of extreme altitude such as that encountered above Base Camp.

'A small percentage of the population experience more challenging symptoms, and it is likely that Victoria is in this minority.'

The pair, accompanied by mountaineer Kenton Cool, had reached Base Camp on April 21 after pre-expedition training in Nepal, the Andes and the Alps.

The track cyclist-turned-jockey won gold at the 2008 and 2012 Olympic Games

After the second of three days on an acclimatisation climb, Pendleton was advised not to continue.

Dubbed 'Queen Victoria', Pendleton, from Stotfold in Bedfordshire, admitted in December that she was taking part in the challenge because she was 'probably having a midlife crisis'.

She also confessed that husband Scott Gardner, 42, the former Team GB sports scientist, would have preferred her not to embark on the adventure with former Countryfile presenter Fogle.

'In an ideal world, he would like to be able to stop me, but he knows that won't make me happy,' she said.