Most women will agree that any birthday launching her into a new decade is likely to be traumatic. When I turned 30, I was disappointed my career wasn't following the path I had mapped out and that I still rented, rather than owned, a house.

The day I turned 40 I was panicking that I was still single, facing a life on the shelf and that my window for having children was getting ever smaller.

A couple of years after that I was in full meltdown - a state of mind that led to me making some very stupid, costly and dangerous decisions.

Scroll down for video

Claudia always assumed that she would meet someone and that motherhood would follow, but it never happened

So, when I tell you I'm still single, and childless, you'd have thought turning 50 a few weeks ago would have pushed me over the edge. I certainly did.

But the dramatic fallout I anticipated never happened - and the penny has suddenly dropped as to why. It's because by the time you reach 50, it's game over on the baby front.

A woman in her mid to late-40s may still be pursuing children (as I was), but after we turn 50, Mother Nature intervenes. She's acted as umpire, taken the decision out of your hands and brought the shutters down. And, my word, it feels good!

Instead of the crippling depression I thought would overwhelm me as a single, childless fiftysomething, I feel calm, happy - and massively relieved.

Things could have been so very different, though. I could have been welcoming in my 50th birthday as a single mother with a five-year-old son or daughter (or even twins) by my side. Because those costly and dangerous decisions I mentioned were the three rounds of IVF I underwent in my 40s to try to have a child - the last one just shy of my 45th birthday.

In total, I spent £30,000 (raised by taking a loan against my flat) trying to conceive a child I now feel hugely glad not to have had.

In fact, when I ask myself what would I rather have woken up and stared at on my 50th birthday - a rosy-cheeked pre-schooler or an extra 30 grand in the bank - the healthy account wins hands down.

Claudia Connell, 50, was so desperate for a baby that she spent £30,000 on IVF. She was in meltdown about being childless, which led to her making some very stupid, costly and dangerous decisions

Today, one in four women is single (having never married) at my age, while one in five is also childless.

At a glacial pace, society is starting to accept that it is possible to be a happy, fulfilled woman who is neither a wife nor mother. But over the past 15 years or so I felt judged and pitied for not being settled or having reproduced.

There were times when I could have told certain friends or family members that I'd single-handedly cured cancer or solved the Middle East crisis only for them to reply: 'Yes, but have you got a boyfriend yet?'

Of course, I had always assumed I would meet someone, marry and take the more traditional route to motherhood. But once I entered my 40s, I felt I had taken waiting to meet my Mr Right to the wire and it was time for Plan B.

Perhaps that's why, aged 41, I made an appointment at a fertility clinic in London with a view to having intra-uterine insemination (IUI) with donor sperm.

20 per cent... ... Is the number of women aged 45 in the UK don't have children Advertisement

The doctor there told me that, at my age, I was wasting time and should go straight to IVF. Despite what many believe, a woman's chances of getting pregnant after 40 are slim and, although more expensive, IVF is more successful than IUI.

Strict regulations in the UK mean sperm donors are in short supply, whereas the rules abroad are more relaxed and there are plenty to choose from. So I opted for a clinic in Athens that treated a lot of single British women.

At my consultation, the doctor scanned me and spotted a uterus full of fibroids (non-cancerous growths). He advised me to have them removed to improve my chances of carrying a child to term. Unable to secure the surgery on the NHS, I had it done privately at a cost of £8,000.

I didn't tell anyone about my operation because I didn't want anyone asking questions. So I went to hospital alone and then struggled home again, in agony, with my overnight bag.

A few months later, aged 42, I underwent my first IVF cycle, costing £6,000, using my own eggs. I had done my research and discovered that my chances of success were less than three per cent. But I went ahead anyway after selecting a 28-year-old Greek doctor as my sperm donor.

She believes that in hindsight, her childlessness shouldn't have bothered her so much, as she was happy living in a beautiful flat and dating casually - which she prefers to serious commitment (stock photo)

The cycle didn't work; deep down, I knew it wouldn't.

I had joined an online forum for older women trying to conceive. Whenever one of them had a failed cycle of IVF they wrote of their despair. When my test was negative, I felt totally indifferent.

Initially, I had no plans to try again. But a year went by and I found that, at 43, instead of being asked, 'When are you going to have children?' the question was: 'So, you're not going to have children, then?'

With hindsight it shouldn't have bothered me so much. I should have told people to mind their own business because I was happy. I lived in a beautiful flat, earned a comfortable living and was travelling all over the world. I was casually dating, something I have realised I prefer to any serious commitment.

Instead, I decided to have another crack at IVF.

Many of the women on the forum I was a member of were having success using the donated eggs of much younger women, rather than their own.

Yet again I travelled to Athens to have a cycle of IVF using eggs donated by a 26-year-old Polish teacher and the sperm of a 19-year-old Danish student. The protocol for IVF with donor eggs is different. It necessitates switching off your natural cycle, stopping ovulation, and, therefore, plunging your body into menopause.

A ticking biological clock drives women to panic. I've seen friends marry just to have children, only to be lumbered with men they despise

Suddenly, a decade before I should have been experiencing such things, I ached all over. The hot flushes and night sweats were unbearable and I felt dizzy and lightheaded from all the drugs I was pumping into myself. Despite the youth of both my donors, that cycle - which had cost me around £8,000 for the drugs, blood tests and travel expenses - also didn't work.

At that point, I should have drawn a line under things and embraced a life without children. Instead, I had one more roll of the dice two years later with yet another £8,000 cycle.

I still ask myself what on earth I was thinking. My only answer is that I don't like to fail and that I had read that the majority of women conceive within three cycles of IVF.

This time, nudging 45, the clinic threw everything at it. My egg donor was a 20-year-old Russian student and my sperm donor a 26‑year-old Portuguese architect. We upped the drugs and threw steroids and an intravenous immune-suppressing cocktail into the mix.

I ballooned in weight and, thanks to the steroids, my face looked like a squishy cushion. Still, the consultant felt certain this cycle would work.

The best eggs had been selected and fertilised with the sperm and transferred at day six, the latest possible time you can transfer an embryo - the theory being that any embryo that has reached that stage is super-healthy and more likely to implant in the womb.

She would rather have the £30,000 she spent back in her bank account than have a child

The embryos were perfect and I would have opted to have just one transferred but, encouraged by the clinic, I went for two to increase my chances, even though it meant the terrifying prospect of twins.

Then something strange happened. During the two weeks you have to wait before finding out if you are pregnant, I gradually came to the conclusion that I did not want children after all. I loved my life without them and felt sure I would be a selfish mother. I found myself becoming increasingly irritated by other people's children and I was having horrific nightmares about giving birth to horribly deformed babies.

Women on the IVF forum who'd given birth were posting nightmare tales of sleepless nights, ruined bodies and lost careers - something I couldn't afford to risk.

Instead of doing everything I could to boost my chances of success I was doing things that could sabotage it: I drank alcohol, I had hot baths and I went for long, body-punishing runs.

When the day came to do the pregnancy test, I didn't bother. I had a feeling the cycle had worked and I wanted to delay seeing 'pregnant' on the test for as long as possible.

I didn't do it the next day either. It was only after the doctor treating me insisted that I find out the result that I tested in my bathroom at home and saw it was positive. I didn't even need to wait the three minutes, it came up instantly. Perhaps it was faulty?

I immediately did a second test only to get the same instant result.

I experienced that feeling where your stomach flips and my heart started to race out of control.

As I sat in the bathroom in shock, I even started to wonder if I should continue with the pregnancy, despite the £30,000 and years of agonising involved.

In the end, the pregnancy turned out to be a 'chemical' one - meaning that the embryo doesn't develop and is lost.

Five years on, those crazy years of trying to conceive feel like an out-of-body experience. I'm angry at myself for spending so much money and for taking such risks with my health (I never came out of menopause after my last cycle of IVF).

Just weeks into my sixth decade I feel like I've turned a corner. I'm so happy my life has worked out the way it has and I am excited, not fearful, about the future.

Dr Vivian Diller, a psychologist who specialises in women and ageing, tells me my feelings of contentment in middle age are common.

She says: 'There is a turning point for women, beyond which they actually start to feel better.

'Young women see this as putting a rose-tinted hue on a situation, but I'm finding it more and more with patients of your age: they feel comfortable in their skin and with their choices in a way they never did before.

And when I consider my friends' marriages, I don't find myself looking down from my lonely shelf and wishing for what they have

'Single, childless women are great at filling their time and making sure they're surrounded by a family of friends. But mothers in their 50s can find themselves alone, bereft and unable to cope with life.

'That's where a childless woman has the upper hand and the benefits of not having any children become clearer.'

At 50, I also think it's unlikely I will ever marry - and I'm OK about that, too.

Thankfully, all the people who used to harass me about not having a significant other are off my case. When you're single over a certain age (46 in my experience), suddenly people stop asking if you've met anyone.

And when I consider my friends' marriages, I don't find myself looking down from my lonely shelf and wishing for what they have.

Many of them are unhappy. I'd go so far as to say that some of them even loathe their spouses. One knows her husband is having an affair but she doesn't care because it keeps him out of her hair. Why would I want that for myself?

Should she be in the market for marriage, a single woman over 50 is likely to make wiser, more considered choices than she would have ten years previously.

A loudly ticking biological clock can drive women to make rushed decisions. I've witnessed two friends marry in a panic at 39 to have children, only to be lumbered now with men they don't love or respect.

At 50, you can take your time. No panic for a whirlwind romance; no pushing for that proposal or honeymoon baby and then ending up saddled to a man you barely know.

Yes, technically, someone my age could pay a small fortune to a shady IVF clinic willing to treat women in their 50s, but I won't be one of them. Right now, being single and childless at 50 is not the huge pity party I thought it would be.