Ann Daniels, 32, part of an all-female relay team trying to reach the Pole, fell through the ice as she skied with the other women. She recalled: "We knew it was thin ice, and when the ice started breaking up I knew I was going to fall in. I couldn't turn round and go back.
"Gradually I started to go down and down and down. Luckily my head didn't go under. All I could think about was how I was going to get out."
Facing death, she remembered the advice her husband, Jez, had given her before she set off. "When I left my husband, he said to me, 'If things get bad, stay calm'. I started to pull myself out and on the third attempt I managed to haul myself out.
"When I was in the water, my thoughts were too mechanical to fear for my life. Afterwards I only thought about getting warm."
Mrs Daniels, from Bradford, was speaking after arriving at Heathrow having successfully completed her part of the McVitie's Polar Relay, and was looking forward to being reunited with her three-year-old triplets Joseph, Lucy and Rachel.
She said it had been a difficult decision to leave them at home with her husband, but she added that they had been her inspiration. "I have so much to tell them now and so much to teach them, and my journey will be a lesson for them in later life. I wanted to teach my children that you have to live life to the full and grab every opportunity that comes along. I would love them to have the chance to do something like this in the future."
Her husband, a 35-year-old safety officer, said: "Ann had always wanted to do something like this and I encouraged her to go. But we would not risk doing anything like this together, because that would risk the children's future.
"If you asked the children where their mother was, they would have told you she was in the North Pole. They are very excited about her coming home," he said.
Returning to Britain yesterday with Mrs Daniels after more than a month away from home were Claire Fletcher, 31, from County Wexford in the Irish Republic, Jan McCormac, 27, from Sunbury, Surrey, and 35-year-old Sue Fullilove, from London.
They were the first of five four-strong teams tackling their stretch of the 1,000-kilometre trek to the Pole. Scaling house-sized pressure ridges on what was regarded as the toughest leg, they battled 60 miles across the ice cap in 16 days - twice as far as they had been scheduled to go.
Ms Fullilove also took an unwelcome dip in the Arctic waters just a few days before Mrs Daniels' plunge."It was a very windy day with poor visibility. I put my foot on a patch that looked as though it was frozen and fell through up to my waist," she said.
Back on solid ice, she said, she rolled herself in the snow in temperatures of about -30C to get rid of the worst of the water.
Despite the dangers of the gruelling trip, all four women said they had enjoyed the experience and hoped to return to the Arctic.
Mrs Daniels said: "It was so exciting, it was just fantastic. You felt on a high the whole time."
The second team of the McVitie's Polar Relay is now tackling the second leg of the expedition, which is due to reach the North Pole in June.