We need to banish the myths about "late" pregnancy. Photo: Getty Images
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What's wrong with older mothers? Nothing. Time to dispel the "fertility cliff" myth

We read between the lines of newspapers' scare stories about infertility and "late" pregnancy to find the science doesn't back them up at all.

There has been a fanfare of publicity, mainly involving ova, over the past month. Frontpage headlines splashing on differing deadlines for when a woman should have children. According to the Mail, Telegraph and Mirror, among others, women should start having children before 30,  or by 30, or before 37 (which is it, guys?) to avoid the risk of infertility:
 

 

 


Alternatively, according to the papers, women should freeze their eggs by the age of 35.

This is irresponsible scaremongering. It also undermines the biological complexities associated with a women’s fertility, which is further complicated by socio-economic factors, as well as the sex and gender hierarchies that still exist.

In a new study published in Harvard Business Review, sociologists Pamela Stone, Robin J Ely and Colleen Ammerman surveyed more than 25,000 men and women who graduated from Harvard Business School over the past several decades. Around 40 per cent of the "Generation X" and "Baby Boomer" women said their spouses’ careers took precedence over theirs. Compare that with men, where more than 70 per cent of Generation X and Boomer men say their careers are more important than their wives.

And the numbers on childcare responsibility may induce hyperventilation: 86 per cent of Generation X and Boomer men said their wives take primary responsibility of childcare. And the women are agreeing: 65 per cent of Generation X women and 72 per cent of Boomer women – most of whom work full-time – say they are prepared to do most of the childcare in their relationships.

It seems society is still, whether consciously or not, conforming to outmoded notions of which behaviours are masculine or feminine.

In the UK, it’s not generally biology that drives a woman's approach to reproduction; it’s the access to effective contraception, giving women the choice to construct their lives around partners, careers and friendships. Although hotly-debated, having children later in life is neither good nor bad – it’s autonomous. A decision entirely dependent on the person in question. 

One common argument against older mothers (30+) is their inability to get pregnant and give birth to a healthy child. This simplifies and distorts the science around fertility, and this is further perpetuated by the media for the sake of a sensationalist headline.

Delving deeper into the truths about fertility: the stats and scientific reports

The Office for National Statistics (ONS) reports that the total fertility rate (TFR) in 2010 for all four constituent countries in the UK was higher than a decade previously. After a steady decline in TFR through the Nineties, there was a gradual increase from early 2000s onwards – with the exception of 2009. The drop in fertility experienced by all UK constituents in 2009 is most likely related to the Great Recession. Fertility in England and Wales peaked in 2010 with the highest fertility rate since 1973.

Total fertility rate in the UK and EU15 (1985 to 2010). Graph: ONS

The ONS reports that in 2010, the average age for a woman to give birth has steadily increased over the last 25 years. In Northern Ireland it reaches 30 years, 29.6 in both Scotland and England and 28.9 in Wales.

Age-specific fertility rates the UK (2010). Graph: ONS

The ONS reports that in 2012, almost half (49 per cent) of all live births were to mothers aged 30 and over. More specifically, 29 per cent of births are to women aged 30 to 34, 16 per cent are to women aged 35 to 39, 4 per cent are to women aged 40 to 44 and less than 1 per cent are to women over 45. One in 25 babies are now born to those over forty, a four-fold increase in 30 years.

Live births by age group of mother (1938 to 2012). Graph: ONS

The term "period of optimum fertility" doesn’t mean a woman becomes barren the second she turns 35. If a woman wants just two children, the chances of her conceiving in her mid to late thirties still remain high.

"It is important to remember that the great majority of pregnancies in older women are relatively uncomplicated and end quite satisfactorily," says WR Cohen in a 2014 commentary published in the British Journal of Obstetrics and Gynaecology

In a 2004 paper published in Obstetrics and Gynecology, statistician David Dunson of Duke University and colleagues found that if a woman has sex twice a week, 82 per cent of woman aged between 35 and 39 would fall pregnant within a year.

The frequency here is important because if a woman had sex once per week instead of twice, "the rates of infertility increase substantially to 15 per cent, 22 to 24 per cent and 29 per cent for women aged 19 to 26, 27 to 34, and 35 to 39 years, respectively".

The paper concludes: "Increased infertility in older couples is attributable primarily to declines in fertility rates rather than to absolute sterility. Many infertile couples will conceive if they try for an additional year".

So women in their thirties might have to try harder to get pregnant, particularly if their partner is also in his late thirties. However, their age alone is unlikely to shut down their fertility.

Population-level data cannot predict when in individual woman will experience infertility. A woman in her late thirties may experience infertility, not because it’s common for women of her age, but because she is atypical (eg, premature menopause affects one in 100 women before the age of 40, and 5 in 100 women before the age of 45).

Therefore it is misleading to automatically associate infertility with age – like any problem that may occur in the human body, premature menopause is a problem with oestrogen production.

The additional complications of pregnancy and birth for women over 35

2005 study in Obstetrics and Gynaecology reports that:

The majority of studies are optimistic with regard to maternal and neonatal outcomes' in older mothers. This study found that ages 35 to 39 were associated with a statistically significant increased risk for fetal/neonatal congenital anomalies, gestational diabetes, placenta praevia, macrosomia, and caesarian delivery. Crucially, however, the clinical significance of these associations in practice was less clear. That is, while women aged 35 to 39 years were significantly more likely to experience one of these outcomes statistically, the level of increased risk was not overly large and should be interpreted cautiously.  

How foetuses are affected by later maternal age

Most of the common risks associated with later maternal age are foetal anomalies, particularly Down's, Edwards' and Patau syndrome. However, about 75 per cent of babies with Down’s syndrome are born to women who are under 35. This is because older women tend to have fewer babies. Despite this, the risk of any woman having a child with a foetal anomaly is low: 99 out of 100 per cent of women will not have a pregnancy affected by Down’s syndrome.

Older women are more likely to have twins or triplets, which, as well as having a higher risk of birth defects (5 per cent higher than singleton pregnancies), are at risk of growth restriction and preterm birth – these risks are associated with cerebral palsy and learning difficulties.

Moreover, women are more likely to suffer from multiple illnesses like diabetes and high blood pressure if they carry more than one baby. If the illnesses are thought to be a serious threat to the mother or babies, the clinician may suggest an abortion of the foetus(es). In general, there is a one in 25,000 risk of maternal mortality during singleton pregnancy or birth versus a two in 25,000 risk of maternal mortality during twin pregnancy or birth, and so on.

Moral of the story?

Doctors like Geeta Nargund need to tread carefully when advising a woman on the best time to have a child. It is important to be honest – yes, women who are below 30 are likely to conceive more easily, but women in their thirties and fourties have no problem conceiving either – and this fact shouldn’t be brushed under the carpet. 

Part of this honesty means we should not blow the problem out of proportion by intentionally presenting the worst-case scenario, scaring women in their early thirties into rushing into pregnancy.

The way things are going, women are likely to have children in their mid to late thirties, and the most likely outcome of that is that most pregnancies, births and babies will be healthy. 

In fact, women don’t respond to media headlines, scientific articles or what a bloke from the Royal Society says; they base their circumstances on those around them. And what they’ll find is that having children in your thirties is quite normal.

As the British Pregnancy Advisory Service (BPAS) puts it in a briefing on older mothers: "Being aware that fertility treatment exists as a last resort does not encourage women to 'put off' having babies, just as knowing that abortion is there when contraception fails does not stop women from using contraception."

BPAS adds:

If policymakers are worried by the consequences of later maternal age, they should be focusing on supporting prenatal screening services, preparing maternity services to be better able to cope with obstetric complications, and funding decent miscarriage care and fertility treatment. What they should not be doing is nagging women to get pregnant before they are ready, just so they fit neatly into the "period of optimum fertility"".

Tosin Thompson writes about science and was the New Statesman's 2015 Wellcome Trust Scholar. 

This article first appeared in the 01 July 2015 issue of the New Statesman, Crisis Europe

Photo: Getty
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The campaign to keep Britain in Europe must be based on hope, not fear

Together we can show the world a generous, outward-facing Britain we can all be proud of.

Today the Liberal Democrats launched our national campaign to keep Britain in Europe. With the polls showing the outcome of this referendum is on a knife-edge, our party is determined to play a decisive role in this once in a generation fight. This will not be an easy campaign. But it is one we will relish as the UK's most outward-looking and internationalist party. Together in Europe the UK has delivered peace, created the world’s largest free trade area and given the British people the opportunity to live, work and travel freely across the continent. Now is the time to build on these achievements, not throw them all away.

Already we are hearing fear-mongering from both sides in this heated debate. On the one hand, Ukip and the feuding Leave campaigns have shamelessly seized on the events in Cologne at New Year to claim that British women will be at risk if the UK stays in Europe. On the other, David Cameron claims that the refugees he derides as a "bunch of migrants" in Calais will all descend on the other side of the Channel the minute Britain leaves the EU. The British public deserve better than this. Rather than constant mud-slinging and politicising of the world's biggest humanitarian crisis since the Second World War, we need a frank and honest debate about what is really at stake. Most importantly this should be a positive campaign, one that is fought on hope and not on fear. As we have a seen in Scotland, a referendum won through scare tactics alone risks winning the battle but losing the war.

The voice of business and civil society, from scientists and the police to environmental charities, have a crucial role to play in explaining how being in the EU benefits the British economy and enhances people's everyday lives. All those who believe in Britain's EU membership must not be afraid to speak out and make the positive case why being in Europe makes us more prosperous, stable and secure. Because at its heart this debate is not just about facts and figures, it is about what kind of country we want to be.

The Leave campaigns cannot agree what they believe in. Some want the UK to be an offshore, deregulated tax haven, others advocate a protectionist, mean-hearted country that shuts it doors to the world. As with so many populist movements, from Putin to Trump, they are defined not by what they are for but what they are against. Their failure to come up with a credible vision for our country's future is not patriotic, it is irresponsible.

This leaves the field open to put forward a united vision of Britain's place in Europe and the world. Liberal Democrats are clear what we believe in: an open, inclusive and tolerant nation that stands tall in the world and doesn't hide from it. We are not uncritical of the EU's institutions. Indeed as Liberals, we fiercely believe that power must be devolved to the lowest possible level, empowering communities and individuals wherever possible to make decisions for themselves. But we recognise that staying in Europe is the best way to find the solutions to the problems that don't stop at borders, rather than leaving them to our children and grandchildren. We believe Britain must put itself at the heart of our continent's future and shape a more effective and more accountable Europe, focused on responding to major global challenges we face.

Together in Europe we can build a strong and prosperous future, from pioneering research into life-saving new medicines to tackling climate change and fighting international crime. Together we can provide hope for the desperate and spread the peace we now take for granted to the rest of the world. And together we can show the world a generous, outward-facing Britain we can all be proud of. So if you agree then join the Liberal Democrat campaign today, to remain in together, and to stand up for the type of Britain you think we should be.