In my 30s I had it all, a partner, high-flying job and plans to start a family. But my dreams of motherhood were dashed in a decade of failed IVF, Then I lost the man of my dreams. Could Everest heal my broken heart?

I was on top of the world. Literally. The summit of Everest, 8,848-metres high. It had taken six gruelling days and nights to get there after leaving base camp and the final hours along the summit ridge had been terrifying – the rocky track as thin as thread with a vertical drop either side. Dead bodies littered the way.

When I finally reached the prayer flags fluttering in the wind at the top, I sat down exhausted.

The view was unarguably magnificent – blue sky against white snow, surrounded by the most glorious mountains in the world. I hadn’t expected to feel triumphant. But I thought there would be a sense of relief that I’d finally made it.

Instead, I just felt numb. And I knew I still had to get down. Descending high mountains is just as difficult and dangerous as climbing up them. As it turns out, I was right to be anxious, something terrible was yet to happen.

I wondered how I got there. A 51-year-old woman from north London who is the most unlikely athlete.

At school, I was the arty one, not the sporty one. I never wanted to be a mountaineer. But somehow I had become a record-breaking adventurer. The first woman in the world to achieve ‘The Sea, Street, Summit Challenge’ – which is to swim the English Channel, run a road marathon and summit Mount Everest.

However, this wasn’t what I had always wanted. What I always wanted was to be a mother.

Jessica Hepburn, the first woman in the world to achieve ‘The Sea, Street, Summit Challenge’

Ms Hepburn trained for six years and made three attempts before reaching Everest's summit

My long, hard journey to the summit of Everest started when I was 34. The day my partner, Peter, and I looked at each other and said: ‘Let’s make a family.’ We had been together for several years. We both had successful careers in the arts world. I had recently become Chief Executive of a London theatre – the Lyric Hammersmith – and I mistakenly thought I was one of the women who could ‘have it all’.

So we threw away the contraception and started trying. It was fun at first - making love for a purpose as well as for pleasure. Like so many couples we thought that soon we’d see a double line on a pregnancy test.

But after a year nothing had happened. We went to our first fertility clinic and were diagnosed with ‘unexplained infertility’. Around a third of all couples who struggle to conceive receive this frustrating diagnosis. We started on IVF. We got pregnant first time. But lost the baby early on. We went through another round. The same thing happened.

IVF was the first gruelling physical and mental endurance journey I undertook. It was a rollercoaster I rode for ten years, mostly in secret. Infertility is shrouded in shame. I didn’t tell family, friends or colleagues.

My job was often glamorous, mixing with famous directors and actors. But at first night theatre parties, behind my smiles for the camera, I was going through the saddest years of my life.

Miscarrying my babies in public toilets, sometimes tying a jumper around my waist to hide the blood and carrying on as if nothing had happened.

The façade cracked when a pregnancy was discovered as ectopic at three months. A perfect baby but not in my womb: in my stomach. An emergency operation saved my life. But pregnancy loss and infertility is barely recognised as an injury, illness or bereavement. As soon as I was discharged from hospital I went back to work.

The worst part of all was what it did to my mental health. I felt like a failure as a woman. I grew distant from my friends as they had their own families. The pain of their happiness too much to bear. I thought I would never be happy.

In total we spent over £70,000 in our pursuit of parenthood and got into debt to pay for it. But in the end the closest I ever came to becoming a biological mother was a cluster of cells. The only evidence the scars across my tummy from my ectopic emergency.

Aged 43, I instinctively knew it was time to give up on my own eggs. Around the same time my relationship with my partner, Peter, started to break down. Perhaps if we had stayed together we could have explored an alternative route to parenthood – adoption, egg or sperm donation, surrogacy. But we separated. It broke me: I fell into the abyss.

I was in my forties. Childless, single and alone. I didn’t know what I wanted from life anymore.

I had a fabulous career, but it wasn’t making me happy. So I gave up my job. I moved back to my childhood home to live, and care for my elderly mum. That’s when I started to exercise my way out of heartbreak.

I’d never swum in open water before so swimming the 21 miles that separated England from France was an odd choice. I couldn’t even swim very well. But I had enjoyed going to our local pool as a child - and it was a memory from then that sparked the idea.

She was in her forties, childless, single, not knowing what she wanted from life

Ms Hepburn has written books and toured schools raising awareness of fertility issues

Back in the 1970s and 80s swimming the English Channel made headline news. When I failed to get a place in my school swimming gala I told my disappointed dad that it didn’t matter because one day I was going to swim the Channel instead.

I loved my dad so much and I wanted to make him proud. He would have made a wonderful grandfather but after suffering a series of strokes he died in 2012 on the day I received the negative result of one of my final rounds of IVF.

I trained for two years - hours and hours doing drills in the pool throughout the winter, and then in the summer in Dover Harbour. When I achieved my qualifying swim of six hours in water below 16 degrees – I was ready to make an attempt.

I began my swim out of sadness on 2 September 2015 at 1.30am. It became my own version of giving birth - 17 hours 44 minutes and 30 seconds of labour in the sea. I suffered with violent vomiting, jellyfish stings all over my body and face. But when my feet finally touched the sand in France, all the pain was eclipsed by euphoria.

The adrenalin buzz of achieving something so big had got me, so I then set out to run the London Marathon. It had been on my bucket list but I had never seriously considered it because I am a rubbish runner.

When I started training a stranger shouted out at me that I must get exhausted running so slowly. On 23 April 2017, every step of the 26.2 miles from Greenwich to the Mall was a slog and I eventually finished in 5 hours and 27 minutes. There will never be a sub four in me.

But on the positive side, I had started using my challenges to raise awareness for fertility causes - writing books and touring to schools across the country to tell my story.

I want young people today to learn more than ‘how not to get pregnant’. They need to know the warning signs of fertility problems; the impact of age on pregnancy success; the limits, costs and ethics of reproductive science.

And then, finally, I embarked on the biggest journey of my life: to the top of the world. I had heard that very few people had swum the Channel and summitted Everest and that no woman had achieved the ‘Sea, Street, Summit Challenge’ – running a marathon as well. I wanted to give it a go.

I was under no illusion about the dangers. Every year a few hundred people attempt to climb the mountain and several die.

It was going to be especially hard for a middle-aged woman who knew nothing about mountaineering. I had never put on a harness, or tied myself to a rope. I started training – climbing all the highest mountains in the UK, and around the world.

I spent hours going up hills with a pack on my back. This inspired me to take on another endurance challenge far more suited to an arty girl – listening to every single episode of my favourite radio programme – Desert Island Discs.

The show’s castaways became my companions – their wisdom and music fuelling me. They inspired me to start creating playlists for every aspect of life. For the mountains; for the mornings; for the sun, wind and rain. Music to cheer me up when I was feeling down. To push me through a final mile.

I also start creating playlists for my family – my parents, grandparents, Peter. And I created a playlist for ‘Molly’ our longed for, imagined child. For her I chose Beethoven’s ‘Ode to Joy’ because all every mother wants is for their child to be happy. Creating these playlists brought me joy and has enabled me to cherish my family – including those I’ve lost and never had at all.

It took me six years of training and three attempts to summit Everest – whom I now call Chomolungma which is her original Tibetan Sherpa name and means ‘Mother Goddess of the World’.

The first try was a non attempt – in 2020 two weeks before I was due to fly to Nepal the mountain was closed due to Covid. I went back in 2021 but was unable to summit. I got sick but also wasn’t fit enough.

I returned for a final time in 2022. My six-day climb began with crossing the Khumbu Icefall. A tumbling cascade of giant blocks of ice, which at any moment can crash down and obliterate you. You have to cross cavernous crevasses with hundreds of metres of blackness below you on lightweight wobbly metal ladders wearing crampons. It’s like treading a tightrope in stilettos. I projectile vomited for 11 hours until we reached Camp 1.

The sickness weakened me and when we reached Camp 2, I had to rest and recover for two days. And from there we still had to reach Camp 3 up the legendary Lhotse Face, a near vertical ice wall, and to Camp 4 on the South Col from where you commence the final ascent – which for me was another 13 long hours upwards through the night.

At 7.30am on the 14 May 2022, I finally made it. But reaching the top of a mountain is only half of the journey. My descent was to become the biggest test of all. Several hours later, at 8,000 metres in the Death Zone – so called because it is too high for helicopter rescue and there isn’t enough air to survive for more than a few hours – I was involved in a freak accident.

Somebody’s oxygen cylinder came hurtling down the mountain, knocking me over and breaking my left leg. Most climbers need at least two bottles of oxygen to reach the summit. The extra bottles are carried on the back of your bag or, sometimes, shamefully thrown away when finished.

I’ll never know whether the bottle was dislodged or discarded. But the result was the darkest two days of my life in which I looked death in the face.

Everyone who climbs Everest is attached in single file to the same safety rope (without it the blow would have knocked me off the mountain). There was someone from my team in front of me and someone behind, and for a while they did what they could to help.

They took off my pack and carried it for me. But the situation was highly stressful for all of us as the injury had made me a life-threatening liability and everyone’s oxygen was running out. I could hardly move and at one point told them to leave me there to die and save themselves.

I crawled to Camp 4 where I passed out and when I woke up I discovered I had lost my sight due to snow and altitude blindness. This added an extra layer of terror.

Thankfully it returned after a couple of hours but even then the ordeal was far from over. I still had get down to Camp 2 where I could be rescued by helicopter. A descent that might usually take a few hours took a whole day – every slow painful step a game of Russian Roulette, my only support in that time Ibuprofen.

When I finally got to the relative safety of Camp 2, I collapsed and all I remember after that is lying in a tent vomiting.

The next day the weather was terrible and it was touch and go whether a helicopter would be able to land but suddenly I heard its thrum. I was carried to it in a frantic blur of sherpa, ice and pain and flown to hospital in Kathmandu.

My accident is not something I’d ever wish on anyone. But nor would I change it. Facing death has made me want to live. And one of the greatest gifts of my adventure from sea to summit is the renewed and profound relationship it has given me with Nature.

For a long time, I felt like she (Nature) didn’t love me because she wouldn’t give me a baby. Now I believe she does and saved my life – because all my injuries were man-made and if the weather hadn’t remained clement I would have surely died.

My adventures have turned the negative experiences of my life into positive. They have given me something else to focus on and the hardness of them has given me more strength to face everyday ups and downs.

I have become an activist for the power of adventure to improve your mental and physical health (including micro adventures closer to home and less dangerous).

The key is doing something new that requires effort. It makes you feel energised and ‘alive’. So I may never be a mother. I think I will always be carrying the grief of my personal life in my rucksack.

But in the words of Louis Armstrong, in one of the most selected Desert Island Discs songs of all time, I truly believe that it is (mostly) a ‘Wonderful World’.

• Save Me from the Waves: An Adventure from Sea to Summit by Jessica Hepburn (£17.99, Aurum) is published this Thursday 7 March