Three in four countries face the threat of ‘underpopulation’ by 2050 because of the world’s plummeting birth rates, shock research warned today.
By 2100 this could rise to 97 per cent of all nations, in what experts have described as a ‘staggering social change’.
Powerhouses such as Britain and the US will have to become reliant on immigration to avoid the ‘immense’ consequences the situation threatens, the study in the respected medical journal The Lancet concluded.
Without replenishment of an ageing population, scientists claim public services and economic growth are at risk.
Ever-declining birth rates will also pile extra pressure on the NHS and social care.
Commentators today warned policymakers need to ‘wake up to the fact that falling fertility rates are one of the greatest threats’ to the West.
The threat of underpopulation sparked by ‘baby busts’ is a pet topic of Elon Musk. In 2017, the eccentric Tesla billionaire said Earth’s population was ‘accelerating towards collapse but few seem to notice or care’.
Dr Natalia Bhattacharjee, of the University of Washington’s School of Medicine, said the trends will completely reconfigure the global economy and the international balance of power.
She said: ‘The implications are immense.
‘These future trends in fertility rates and live births will completely reconfigure the global economy and the international balance of power and will necessitate reorganising societies.
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‘Global recognition of the challenges around migration and global aid networks are going to be all the more critical when there is fierce competition for migrants to sustain economic growth and as sub-Saharan Africa’s baby boom continues.’
She added: ‘There’s no silver bullet.
‘Social policies to improve birth rates such as enhanced parental leave, free childcare, financial incentives, and extra employment rights, may provide a small boost to fertility rates.
‘But most countries will remain below replacement levels.
‘And once nearly every country’s population is shrinking, reliance on open immigration will become necessary to sustain economic growth.
‘Sub-Saharan African countries have a vital resource that ageing societies are losing — a youthful population.’
For a population to stay the same size, countries must achieve a ‘replacement’ level fertility rate of 2.1.
In the UK, the birth rate is predicted to fall to 1.3 children per woman of childbearing age by 2100, however.
The rate stood at around 2.2 in the 1950s, dropping to 1.9 in the 1980s.
Currently it stands close to the 1.5 mark.
The US will see a similar downward trajectory as the UK.
Fertility replacement doesn’t account for the impact of migration, meaning overall population levels can still increase in a country despite a drop in fertility rates.
The study also predicted half of all babies will be born in sub-Saharan Africa by 2100.
Fertility replacement, however, doesn’t account for the impact of migration, meaning overall population levels can still increase in a country despite a drop in fertility rates.
While many scientists have warned about the threat of overpopulation on the environment, food and housing supplies, underpopulation is also a challenge.
If unaddressed, it can lead to an increasing ageing population, with a significant proportion needing care and unable to work.
Professor Stein Emil Vollset, fellow researcher, said women in high-income countries who wish to have children must be better supported to maintain population size and economic growth.
‘We are facing staggering social change through the 21st century,’ he said.
‘The world will be simultaneously tackling a baby boom in some countries and a baby bust in others.’
He also warned that some of the poorest and most politically unstable countries in Africa will be grappling with how to support the youngest, fastest-growing population on the planet.
The figures project that by 2050, seven of the top 10 countries with the highest birth rates will be in sub-Saharan Africa.
Niger is forecasted to top the list with a rate of 5.15.
Britain’s fertility rate has been in freefall for a decade, apart from a blip during 2021 put down to a mini baby ‘bounce’ by couples who put their family plans on hold at the start of the Covid pandemic.
Experts believe the trend is partly down to women focusing on their education and careers and couples waiting to have children until later in life.
As fertility is linked to age, this can lead to some women never having children or fewer than they might originally have planned.
The UK’s fragile economy and cost-of-living crisis is also putting people off having children, some believe, evidenced by abortion rates simultaneously spiking.
Others cite the environment, with people fearing that they will worsen their carbon footprint by having a child or that their child will have a bleak future due to climate change.
For men, lifestyle factors like the rising prevalence of obesity in many countries is also thought to be having a downward impact on fertility.
The threat of underpopulation has been a pet topic of Elon Musk, who has preached about it for years.
In 2017, he said that the number of people on Earth is 'accelerating towards collapse but few seem to notice or care'.
Then in 2021 Musk, who has 11 known children, warned that civilisation is 'going to crumble' if people don't have more children.
At Italian Prime Minister Giorgia Meloni's 'Atreju' political festival in Rome in December, Musk also urged Italians to have more children to 'save Italy's culture'.
Later, he added: 'My advice to all government leaders and people is make sure you have children to create a new generation or the culture of Italy, Japan and France will disappear.'
He said: 'We are in danger of no longer having these countries.'
The international research project, published in The Lancet, looked at past, current, and future trends in fertility and live births.
The authors warned that governments must start planning for threats to economies, food security, health, the environment and geopolitical security brought on by the demographic changes.
So what is behind the West's baby bust?
Women worldwide, on average, are having fewer children now than previous generations.
The trend, down to increased access to education and contraception, more women taking up jobs and changing attitudes towards having children, is expected to see dozens of countries' population shrink by 2100.
Dr Jennifer Sciubba, author of 8 Billion and Counting: How Sex, Death, and Migration Shape Our World, told that people are choosing to have smaller families and the change 'is permanent'.
'So it's wise to focus on working within this new reality rather than trying to change it,' she said.
Sex education and contraception
A rise in education and access to contraception is one reason behind the drop off in the global fertility rate.
Education around pregnancy and contraception has increased, with sex education classes beginning in the US in the 1970s and becoming compulsory in the UK in the 1990s.
'There is an old adage that 'education is the best contraception' and I think that is relevant' for explaining the decline in birth rates, said Professor Allan Pacey, an andrologist at the University of Sheffield and former chair of the British Fertility Society.
Elina Pradhan, a senior health specialist at the World Bank, suggests that more educated women choose to have fewer children due to concerns about earning less when taking time off before and after giving birth.
In the UK, three in 10 mothers and one in 20 fathers report having to cut back on their working hours due to childcare, according to ONS data.
They may also have more exposure to different ideas on family sizes through school and connections they make during their education, encouraging them to think more critically about the number of children they want, she said.
And more educated women may know more about prenatal care and child health and may have more access to healthcare, Ms Pradhan added.
Professor Jonathan Portes, an economist at King's College London, said that women's greater control over their own fertility means 'households, and women in particular, both want fewer children and are able to do so'.
More women entering the workplace
More women are in the workplace now than they were 50 years ago — 72 vs 52 per cent — which has contributed to the global fertility rate halving over the same time period.
Professor Portes also noted that the drop-off in the birth rate may also be down to the structure of labour and housing markets, expensive childcare and gender roles making it difficult for many women to combine career aspirations with having a family.
The UK Government has 'implemented the most anti-family policies of any Government in living memory' by cutting services that support families, along with benefit cuts that 'deliberately punish low-income families with children', he added.
As more women have entered the workplace, the age they are starting a family has been pushed back. Data from the ONS shows that the most common age for a women who were born in 1949 to give birth was 22. But women born in 1975, were most likely to have children when they were 31-years-old.
In another sign that late motherhood is on the rise, half of women born in 1990, the most recent cohort to reach 30-years-old, remained childless at 30 — the highest rate recorded.
Women repeatedly point to work-related reasons for putting off having children, with surveys finding that most women want to make their way further up the career ladder before conceiving.
However, the move could be leading to women having fewer children than they planned. In the 1990s, just 6,700 cycles of IVF — a technique to help people with fertility problems to have a baby — took place in the UK annually. But this skyrocketed to more than 69,000 by 2019, suggesting more women are struggling to conceive naturally.
Declining sperm counts
Reproductive experts have also raised the alarm that biological factors, such as falling sperm counts and changes to sexual development, could 'threaten human survival'.
Dr Shanna Swan, an epidemiologist at Icahn School of Medicine at Mount Sinai in New York City, authored a ground-breaking 2017 study that revealed that global sperm counts have dropped by more than half over the past four decades.
She warned that 'everywhere chemicals', such as phthalates found in toiletries, food packaging and children's toys, are to blame. The chemicals cause hormonal imbalance which can trigger 'reproductive havoc', she said.
Factors including smoking tobacco and marijuana and rising obesity rates may also play a role, Dr Swan said.
Studies have also pointed to air pollution for dropping fertility rates, suggesting it triggers inflammation which can damage egg and sperm production.
However, Professor Pacey, a sperm quality and fertility expert, said: 'I really don't think that any changes in sperm quality are responsible for the decline in birth rates.
'In fact, I do not believe the current evidence that sperm quality has declined.'
He said: 'I think a much bigger issue for falling birth rates is the fact that: (a) people are choosing to have fewer children; and (b) they are waiting until they are older to have them.'
Fears about bringing children into the world
Choosing not to have children is cited by some scientists as the best thing a person can do for the planet, compared to cutting energy use, travel and making food choices based on their carbon footprint.
Scientists at Oregon State University calculated that the each child adds about 9,441 metric tons of carbon dioxide to the 'carbon legacy' of a woman. Each metric ton is equivalent to driving around the world's circumference.
Experts say the data is discouraging the climate conscious from having babies, while others are opting-out of children due to fears around the world they will grow up in.
Dr Britt Wray, a human and planetary health fellow at Stanford University, said the drop-off in fertility rates was due to a 'fear of a degraded future due to climate change'.
She was one of the authors behind a Lancet study of 10,000 volunteers, which revealed four in ten young people fear bringing children into the world because of climate concerns.
Professor David Coleman, emeritus professor of demography at Oxford University, told that peoples' decision not to have children is 'understandable' due to poor conditions, such as climate change.
