Wendy Booker’s left side is numb from her toes to the top of her rib cage.

Yet somehow, she has managed to climb the tallest peaks on six continents. For Booker to complete the climbing feat known as the Seven Summits, just one peak remains: Mount Everest, the highest mountain on Earth.

Living with multiple sclerosis, Booker says, is much like climbing a mountain.

“I wanted to show what life with MS is like,” she says. “It’s a struggle. You can’t always get to the top.”

Booker, 54, will strive to become the first person with MS to climb the highest mountain on each of the world’s seven continents when she attempts Everest this spring.

At 29,035 feet, Mount Everest towers above the Himalayas on the border of the south Asian countries of Nepal and Tibet.

A single mother of three who splits her time between Boston and Boulder, Colo., Booker will have plenty of help from Central Oregon climbers.

Booker, who has received international media attention on her quest, plans to climb Everest with Brooke Barnes of Mountain Link guide service in Bend. The two trained earlier this month at Mount Bachelor, practicing ladder crossings while wearing crampons, in preparation for the dangerous Khumbu Icefall on Everest.

Barnes and Booker have reached together the top of three of the Seven Summits: 16,067-foot Mount Vinson Massif in Antarctica, 22,834-foot Aconcagua in Argentina, and 7,310-foot Mount Kosciuszko in Australia.

Booker says she will not climb without Barnes.

“We definitely have bonded in a way that only the mountain can do,” says Barnes, 40. “She’s a really gung-ho woman.”

Robert Link, the owner of Mountain Link, who reached the Everest summit in 1990, will communicate with Booker and Barnes from Everest Base Camp.

Booker climbed Russia’s 18,481-foot Mount Elbrus with Link in 2006.

“(MS) takes good athletes and destroys them,” Link says. “What she’s done is just incredible.”

After experiencing leg numbness, Booker was diagnosed with MS in 1998.

“You think of the worst case, and you immediately picture someone you know who’s in a wheelchair,” she says. “It was from the anger that I said, ‘Before I get in that wheelchair, I’m gonna run the Boston Marathon.’ I knew there was more I had to do.”

An autoimmune disease, MS is an inflammation of the nervous system. More than 400,000 Americans have MS, according to the Multiple Sclerosis Association of America. Currently, there is no cure for the disease, but it is not fatal. Symptoms include an increasing loss of coordination, muscle weakness and numbness.

Booker says her MS is in remission, but she concedes that the disease is “unpredictable.”

Booker notes that before 1993 there were no drugs for MS. But she has taken a daily injection of a drug called Copaxone for the last 11 years to manage the disease. She says she has no visible signs of the illness, just the numbness on her left side, which she describes as a fuzzy, tingling feeling.

Booker, who had started running regularly shortly before she was diagnosed, first ran the Boston Marathon in 2000, finishing in 4 hours, 42 minutes.

“At the time, people with MS were not running marathons,” Booker says.

“Now, many people (with MS) are running marathons and triathlons.”

Since Boston in 2000, she has completed eight more marathons.

Booker was introduced to mountain climbing when she was asked to be part of the first team of climbers with MS to attempt to summit Denali (Mount McKinley) in Alaska.

The group went unguided and did not reach the summit. Frustrated, Booker vowed to train harder and to use a guide the next time. She spent time training in the White Mountains of New Hampshire, and in the Cascade Mountains.

Booker reached the summit of Denali in 2004.

“I thought, ‘What can I do now?’” she recalls. “And that’s when the Seven Summits started to come in.”

Over the next 4½ years, she climbed 19,340-foot Kilimanjaro in Africa, followed by Elbrus, Aconcagua, Vinson Massif and Koscuiszko.

All that remains is the highest and most notorious mountain in the world. Everest is an endless source of controversy for its overcrowding and peril. More than 200 climbers have died on the mountain.

Booker notes that fewer than 25 percent of Everest climbers reach the summit on their first attempt, and she does not plan to force the issue.

“I really feel I know when to say ‘When,’ and Mountain Link respects that,” she says. “We listen to one another. You have to have that trust.”

Because of the MS, Booker has difficulties with balance and dealing with cold weather.

“She’ll deteriorate faster if she gets to a certain point,” Barnes says.

“Sometimes, it just doesn’t allow her to do it. When she gets tired, she’ll drag the left side of her body. That’s when we’ve gone too far.”

Before her MS diagnosis, Booker, who is divorced, worked as an interior decorator. Now, she makes a living traveling the country as a motivational speaker. Sponsors pay much of the expenses for her mountain climbing exploits.

Atop the highest peaks on the planet, she is far from the world of interior design.

“I was very country club, very sorority girl,” Booker says. “And now I’m climbing the highest mountains in the world.

“If I can do this, anybody can do it.”

Seven Summits

A look at Wendy Booker’s quest to climb the tallest mountain on each continent, possibly culminating with an ascent of Mount Everest this year:

June 2004: Mount McKinley (Denali) (Alaska, USA), 20,320 feet.

June 2005: Mount Kilimanjaro, (Africa), 19,340 feet.

July 2006: Mount Elbrus (Russia), 18,481 feet.

January 2007: Mount Aconcagua (Argentina), 22,834 feet.

January 2008: Mount Vinson Massif (Antarctica), 16,067 feet.

November 2008: Mount Koscuiszko (Australia), 7,310 feet.

May 2009 (planned): Mount Everest (Nepal), 29,035 feet.

For more information, visit www.wendybooker.net