My first baby at 51

It wasn't so much the eleventh hour as five to midnight. We had two embryos left in the freezer of a fertility clinic and, by March, I'd be too old to receive them. With two miscarriages and four previous attempts at IVF embryo transfers, it felt like a futile mission, but in February, my partner, Pete, and I decided to give the dice one last roll.

We met in August 2002 on board a flight to Nice. He was on his way to a skydiving course while I was meeting a friend for a walk in the mountains. When I got back to London two weeks later, I emailed to see if he'd landed safely and before long we were spending every weekend together.

On paper we made an unlikely match. I was then 42 and Pete eight years younger. He'd been a soldier, a fireman and a boxer; he does triathlons for fun. I'm more inclined towards yoga and cafe culture, and I'll never convince him of the interconnectedness of everything. Pete wondered if he'd stumbled into a parallel universe when he saw a copy of On Being A Jewish Feminist on my bookshelf.

In terms of physiology and favourable maternal and foetal outcomes, the best age for childbearing is 20-35, but in my 20s I ran from any man who might clip my wings. I wasn't then ready to settle down, though I'd probably have sneered at any woman in middle age who was still trying to have children. I assumed that I could travel the world, have a fulfilling career and still find time to create a family, too. Romance, to my mind, was a path to adventure rather than the prelude to marriage and children, yet at the same time I wanted to raise children in a stable relationship.

I spent much of my 30s recovering from a near-fatal car crash. That's when my two sisters and brother and many of my friends were making babies, but I didn't know if I'd ever fully recover from a head injury and post-traumatic stress disorder, compounded in 1996 by the death of my father, to whom I was very close. I tried to make peace with childlessness, yet always hoped that it would somehow pan out.

I was in my mid-40s before I felt ready for motherhood. Pete was at a different stage. I didn't dare risk unilateral action because I was sure it would end in disaster. But as our attachment grew, and as his own friends and then his younger brother began to procreate, Pete caught the baby bug, too. By then, however, my biological clock was on overtime and with each failed attempt, we became more conscious that we were losing direction and purpose, like two ships blown off course.

It's not as if trying to make a baby was my only focus – far from it – but I was unsettled. I hadn't repainted my fourth floor studio flat for eight years because it had been at the back of my mind that it wouldn't be suitable as a home if we had a baby. I found it difficult to complete any work and have, from those years, two unpublished books and several half-baked films rotting in my file of "Dead Projects". After the second miscarriage, I was so distraught that I spent a year seeing a bereavement counsellor.

As we navigated a confusing range of fertility treatments, Pete and I came up against various barriers, such as the consultant in St Mary's hospital recurrent miscarriage clinic who refused to test Pete because of my age. "Let's draw a line under this," she said to me. I left St Mary's furious and frustrated at having been judged simply for my age, not my follicle-stimulating hormone levels.

People asked if we would consider adoption. I'd have been happy by that point to take care of a Cabbage Patch Kid, but this was a joint venture and Pete didn't feel the same way. I tried acupuncture and had my monthly cycles monitored before we turned to IVF. Unimpressed by the private clinics we visited in London, we looked at options overseas. We spent a small fortune on three stabs at fertility treatment at a clinic in Cape Town, but that produced nothing other than a suntan and buttocks like pincushions after daily injections of hormones.

Back in London in time for my 50th birthday on New Year's Eve, Pete and I accidentally got caught up with revellers in Trafalgar Square and were kettled by police on horseback: a suitable metaphor for my state of mind.

Each time you get pregnant or have a cycle of fertility treatment, you imagine a bright future. Then your hopes are dashed and, once again, you have to reboot. Emotional snakes and ladders. I wanted to give in graciously. Pete wasn't willing to accept defeat so lightly. He found a clinic in Barcelona with a cut-off age of 51. Dreading further disappointment, I vacillated for months. Then, last November, with just one more menstrual cycle left before my next birthday, I could procrastinate no longer. We paid the clinic's advance.

Yet again it didn't work. The clinic extended their deadline by three months for us to use the remaining embryos. I'm not sure why we bothered. It seemed like such a remote possibility, throwing good money after bad. My expectations couldn't have been lower.

Pete was away on the date I was due to take a pregnancy test. I woke in the middle of the night to pee and thought I should use the opportunity to find out. Nothing. I tried to blank out the disappointment and went back to sleep but when I woke again a few hours later and re-examined the white stick, there was a faint pink line where before I'd seen none. I took this to a chemist and asked the pharmacist: "Could I be a little bit pregnant?"

She took one look and laughed. "One hundred per cent pregnant!"

I danced with joy.

A scan showed that both embryos had implanted and we were expecting twins. Bingo! Then, at eight weeks, another scan showed that one of the twins had died. It felt as if history was repeating itself.

The prospect of twins had been very exciting but maybe it was for the best. Having twins greatly increases your risk of pre-eclampsia – a condition thought to be caused by a problem with the placenta, resulting in high blood pressure and protein in your urine, and which can lead to convulsions, even a stroke. Other potential complications of twin pregnancies include gestational diabetes, postpartum haemorrhage, stillbirth and caesarean section.

Even among single pregnancies, if you're older than 40 the danger of pre-eclampsia increases from 3-4% to 5-10%, and rises to 35% if you're past 50. There's also a 20% chance of diabetes among mothers over 50. One study of 539 deliveries found that the risks for low birth weight and preterm babies tripled – and foetal mortality doubled – among mothers over 50 compared with mothers aged 20-29.

We think of women having babies later in life as a recent phenomenon, but in England and Wales, back in 1939, out of 614,479 births, 2,147 babies were born to women aged over 45. The number of older mothers decreased until 1977, when just 454 babies out of 569,259 were born to women over 45. Since then, figures have been rising steadily.

Professor Susan Bewley, consultant obstetrician at King's College London, notes that pregnancies in older mothers are more likely to be as a result of assisted reproductive technology (ART) and that women who conceive via ART have a higher chance of having pregnancy-induced hypertension, gestational diabetes, preterm birth and caesarean section.

While her personal opinion is that the birth of a healthy baby is a joy at any age, she adds, "My professional opinion is that I'm very worried about the increasing health risks to mothers and babies, and I've been around long enough to have seen all the complications associated with advanced age, including maternal and baby death and disability."

Others are more positive. Bill Smith, consultant ultrasound specialist atClinical Diagnostic Services in London, has been involved with infertility and obstetric screening for more than 30 years. He feels strongly that older patients are pushed too readily towards IVF. "They're not given a chance to conceive with ultrasound monitoring of natural cycles. If nature allows women of 42, 43, to get pregnant, then why not allow them to be treated with their own eggs, the same as a 32-year-old? And the same applies to women in their late 40s and even early 50s."

Yes, there's a greater chance of chromosome abnormalities in the foetus for older mothers-to-be, but ultrasound scans during the first trimester screening allow Down's syndrome and other anomalies to be picked up. "When I look at the dozen or so pregnancies that come through our unit each year with patients in their early 50s," Smith says, "to my knowledge very few present problems."

In 2010, out of 723,165 births, 1,758 babies were had by women over 45. Of those, 141 babies were born to 118 women aged 50 and over. And – despite obstetric issues relating to ART, multiple gestations and middle-aged mums – there has not been a single stillbirth in this age range since 2004.

I never gave much thought to the health risks. Maybe I'd have been more circumspect if I had looked at the small print. Fortunately, the worst of my pregnancy-related complaints have been acid reflux and swollen feet, and – claims Pete – I've started to snore.

Agnes Mayall is 50 and, thanks to what she calls "technical assistance", is due to have her first baby in mid-November. Stylish and slim – apart from her bump – she's a lecturer in art history. "I was aware of the health risks and though I thought that what I was doing was mad, what finally allowed me to go ahead was realising that there are moments in life when you do things that are mad."

Mayall was ambivalent about parenthood. "People assume that I wanted a baby above all. In my case that's just not true, but I am very excited to be having one. I used to be terrified that I would be a crap mother and I'm now more relaxed about it. It's not that I think I'll be a brilliant mother, I'm just not afraid of it any more."

Her husband, Ben, an engineer, is seven years younger: "He was 23 when we met." Soon after, Mayall became pregnant. "He was freaked out by it, so I had an abortion. I assumed he didn't want children. He thought that I didn't want children and so we never discussed it. And I began to see that there were other ways to lead a fulfilling life that didn't necessarily involve a family."

The subject of children came up again only when Mayall was in her mid-40s. "That was when we first started to talk about what kind of a life we wanted. That's when we finally got around to asking whether we might want a child. I realised then that Ben was very keen, that this was an experience that he wanted to have, but I'd had no idea before that."

Mayall went to see her GP, assuming that she would be discouraged. "Instead she said: 'Why don't you give it a go?' Two months later I was pregnant. Even though it was something we had consciously decided to try for, I was terrified. I fixed on a fear of losing things that I called freedoms and that, in the process, I would lose my identity."

She had a miscarriage at 12 weeks and another not long afterwards. Devastated by the loss of these pregnancies, Mayall realised that she had spent many years blocking out regrets over the earlier abortion. She was slow to go public about her pregnancy, "partly because I didn't expect it to work, and partly because I felt a bit embarrassed about being pregnant at my great age; but as I did tell people they were all really encouraging, so it became gradually easier, because every reaction was positive. And many of my friends have said how much they would now love to be having a child."

At first I, too, was coy about telling anyone that I was pregnant. Eventually, concern that people might think I'd lost control over my waistline outweighed worries about frowns and raised eyebrows. A few curiosity-seekers have shown an unhealthy interest because of my age, but neither Pete nor I has ever been much bothered by convention and, besides, we're hardly a freak show.

For the people who matter to us, it's been a cause for celebration and extraordinary kindness. My mother is an energetic octogenarian; she's anxious that she won't be capable of much hands-on assistance, so has offered to pay for a doula instead. One neighbour insists on meeting me at Waitrose to carry my groceries. Others bring my laundry up three flights of stairs. And I've taken pleasure in consulting women half my age about whether I should opt for an Ergo carrier or a Baby Bjorn, whether my feet will ever shrink back to their pre-pregnancy size and whether we really need a nappy bin?

I stopped cycling soon after a grumpy van driver crushed me against a parked car when I was seven weeks pregnant. It was a week later that we discovered one of the twins had died. I was full of self-recrimination – was I in any way responsible? – and started travelling by public transport instead. While bus passengers aren't particularly gallant, on the underground there hasn't been a single rush-hour journey when someone hasn't stood up to offer me a seat.

Strangers strike up conversations. "Is it your first?" "When's it due?" "Do you know if it's a boy or a girl?" "Do you have any food cravings?" (Papaya with cottage cheese, chicken yakitori and cherry juice; I've also developed an uncharacteristic appetite for romcoms starring Jennifer Lopez.)

There are many young people in our lives, including seven nephews, two nieces and numerous godchildren. I'd decided not to tell any of the kids that I was pregnant during the first trimester in case it didn't work out, but I was having brunch one Sunday with Clio – my 21-year-old niece – when she went bright red and, shaping an imaginary bump around her own pancake-flat stomach, blurted out: "Naomi, I know… about the baby!" I felt a little churlish for not having told her sooner and registered in that moment that Clio has matured into an honorary sister. Family roles can be dynamic.

All the other women in my family are magnificent matriarchs with beautiful, well-organised homes, while the role I've played until now has been peripatetic and undomesticated. My sisters are both full-time mothers, while I move from project to project, driven by ideas and a deep-rooted streak of activism. I don't yet know how my new status will evolve, but the rest of my family seem almost as thrilled as Pete and I are.

Plenty of my friends don't have children. I can think of only a few for whom this has been by conscious design. I wondered – fleetingly – if there would be any resentment from those for whom it hasn't. However, for everyone who knows how tough a journey this has been for us, our news has been received as a collective triumph.

I'm as anxious as any first-time mother and as I slide from a childless world in which discourse revolves mostly around work and politics into the camaraderie of parenthood, it's reassuring to discover such a rich seam of wisdom, though my eyes do glaze over when experienced mothers offer unsolicited advice about sleep routines and whether to feed on demand. On the other hand, in the changing room at my gym, several women in their late 30s and early 40s, on learning my age, have wanted to discuss their own fertility issues, or relationships that are going nowhere, or how they'd like a baby but have no relationship at all.

It's a terrible modern conundrum, and I'm a little reluctant to be seen as a beacon of possibility because Pete and I have had so much heartache and we're incredibly fortunate to have made it this far. (I'm not alone in this. Another first-time mother in her early 50s declined to be included in this piece because, she said, "what we have is miraculous but we are in the minority to have healthy, normal babies... Nature is against us and I'm not sure I want to be part of encouraging women to leave it so late.")

Alastair Sutcliffe, consultant paediatrician at UCLH and Great Ormond Street hospital, puts it into context: "When I was graduating from medical school in 1987, we were told that an elderly primip – a first-time mother – was anyone over the age of 30. But now the peak age range for all births in this country is 30 to 34. Women have been caught in a feminist-driven trap. This country has tripled its economic output since the second world war by getting women working and into employment."

Social norms have changed, says Irenee Daly at the Centre for Family Research in Cambridge. "We don't expect women of typical university age to want to have children. We socialise them away from that. The 20s are now regarded as a time for exploration, before life's enduring responsibilities take hold." Young men and women still expect to have settled down in a stable relationship and own their own home before starting a family. "And since these things are all happening later, that pushes having children later."

For her doctoral thesis, Daly looked at whether women in their late 20s and early 30s understood the degree to which fertility declined with age and whether they thought that IVF could compensate for the effects of ageing. "There was a perception that it would work out in time. Most of the women I spoke to were shocked to learn that IVF is linked to age, that even in the youngest age group, we're talking about only a 30% success rate. Then they were doubly shocked to see that by 44 it goes down to 5% using one's own eggs."

Freezing eggs doesn't guarantee a viable pregnancy and, as Daly points out, "You have to freeze young eggs, so a woman of 40 saying that she's decided to freeze her eggs – well, what sort of quality are those eggs?"

Young women are not the only ones with a hazy grasp of medical possibilities. It's often assumed that infertility is on the woman's side; and until you're in the market for ART, few people seem to know that it goes beyond IVF to include a wide menu of options such as intrauterine insemination (IUI), intra-cytoplasmic sperm injection (ICSI), gamete intra-fallopian transfer (Gift), pre-implantation genetic diagnosis (PGD), sperm donation, egg donation and more.

Many of the women in Daly's study felt that since people are now living longer, parenting could be spread more evenly over the course of one's life, but while she acknowledges that that is "technically true", she emphasises that our reproductive window has not increased in line with life expectancy: "So whether or not you think you will be kicking around a football at 70 doesn't matter."

In Italy – which has one of the lowest fertility rates in the western world – Professor Brian Dale, director of the Centro Fecondazione Assistita, is used to working with older women. "Women in Italy decide to have a family very late in life, on average well over 30, and it starts to become a little difficult over 35."

Even though the number and quality of eggs decreases with age, Dale favours using women's own eggs whenever possible. "If you get good embryos, we're looking at 18-20% pregnancy rate per embryo transfer." That success rate doesn't vary much if the cycle is spontaneous or stimulated and the more embryos transferred, the higher the likelihood of a pregnancy. "The oldest lady I remember getting pregnant with her own eggs was 46. But most people who come to us aged over 45 are already psychologically primed to go on the egg donor programme."

Sutcliffe describes the rising age of first-time mothers as an epidemic. According to him – whose mother was 45 when she gave birth to his youngest sister – older first-time mothers tend to be university graduates and have higher socio-economic status than average. They are likely to live farther away from their extended families than younger women and rely more on friends for support. According to his research, we older mothers are more resilient and less dependent on others, we tend to have committed relationships with a partner and are financially secure.

"Women who delay childbirth," Sutcliffe says, "have satisfied their personal goals and don't feel they are missing anything." But while older women generally make good mothers, "the one area where they are perhaps less able is to do with physical activity with their children, and there is a slight tendency for those children to be overweight."

To Sutcliffe's mind, of much greater concern than middle-aged women pursuing dreams of motherhood is maternal obesity. "This country is the second most obese in the world," he says. "It's so bad that the maternal mortality rate may even start to kick up. In relation to older mothers, it's a much bigger problem."

He also acknowledges that there is a difference between chronological and biological age (your age in years as opposed to your age at a cellular level). "People don't look younger," he says, "unless they're biologically younger." I've never looked my age. Once a cause for angst, this has now turned into a major advantage. Even so, people ask if I'll have enough energy to run around after a toddler. Often, hanging in the air, is an unspoken concern about whether I'll live long enough to see my child into adulthood. I worry not so much about longevity – so far the genetic lottery has been good to me and my grandmother, at 104, is still going strong – but about how much authority I'll have over a rebellious teenager when I'm nearing 70. I'll face that challenge when it comes.

Our baby is due next week. My nesting hormones are running wild. I've started rounding up muslins and moses baskets, and my hospital bag is already packed.

(http://www.theguardian.com/)