Martina Navratilova said on Friday illness has cut short her attempt to climb Tanzania's Mount Kilimanjaro on the fourth day of a six-day climb to the summit of Africa's tallest mountain.
The 53-year-old, one of the greats of women's tennis, started her climb on Monday, but suffered high altitude pulmonary oedema -- an accumulation of fluid in the lungs -- and was flown to hospital in Kenya's capital Nairobi.
Her doctor said she is expected to recover fully.
"I'm disappointed not to be able to complete this amazing journey. It was something that I have wanted to do for so long, but it was not to be," she said in a statement.
"I am so pleased that we got it going and I will be watching and waiting for news from the climb when they reach the summit tomorrow (Saturday)."
The Czech-born star, who became a US citizen in 1981, was leading a team of 27 climbers to raise funds for the Laureus Sport for Good Foundation charity.
Navratilova, winner of 18 Grand Slam singles crowns, was diagnosed with non-invasive breast cancer early this year. She was later pronounced cancer free following a lumpectomy and radiation treatment.
On November 10 she scaled 55 stories to the top of a city skyscraper in New York to promote her climb of Kilimanjaro, the world's highest free-standing mountain at 19,340 feet.
Navratilova is a member of the Laureus World Sports Academy, an association of 46 of the greatest living sporting legends who volunteer their time to use sport to combat some of the world's toughest social challenges facing young people today such as HIV/AIDS, substance abuse, crime and violence.
Since its inception Laureus has raised over $50 million and supports almost 80 sports-based projects around the world.