Fertility rates are plummeting around the globe and will fall to shockingly unsustainable levels by the end of the century, posing an almighty challenge for the global economy. That's according to a major new study published in medical journal The Lancet, at least. 

The fertility rate is already below the replacement level required in countless nations and, by the year 2100, 97% of countries will be unable to sustain their populations.

Read on to discover the possible economic consequences of the great baby bust and find out what governments are doing to tackle the issue. Plus, we explore if the latest technological advances can save the day...

All dollar amounts in US dollars. 

The "great baby bust" (also referred to as the "big baby bust") is the marked and progressive decline in the fertility rate worldwide.

The fertility rate is the average number of children born to women during their reproductive years. For a country or area's population to remain stable, a fertility rate of 2.1 is required. The global fertility rate has nosedived since 1965, when it stood at over five births per woman. By 2021, it had fallen to 2.4, which is barely above the replacement rate of 2.1. Fast-forward to 2050 and experts are predicting that there won't be a sufficient number of births to sustain the global population.

By then, the rate is predicted to have fallen to 1.83 and will drop again to 1.59 by 2100.

In tandem with fertility rates, poverty levels have plunged since the 1960s.

When countries become wealthier, women's access to education, healthcare, work, and contraception increases. As a result, they tend to have fewer children, with this trend playing out around the world from the late 20th century onwards. Moreover, the decision not to have children is positively embraced in many societies.

Other factors at play include government rulings, such as China's now-defunct one-child policy, the expense of raising children in developed countries, and a wave of eco-anxiety putting people off from having kids. Falling sperm counts are also playing a significant part in the problem. 

More than half of the world's countries and territories already have fertility rates that sit below the replacement level of 2.1, according to the study in The Lancet.

Almost every advanced economy is now unable to sustain its population. As per 2021 figures, South Korea has the lowest fertility rate at 0.82, followed by Taiwan and Andorra at 0.98 apiece.

Singapore's is just 1.20, while Italy stands at 1.21. China's is 1.23, Japan's is 1.26, and Canada's amounts to 1.46. The UK's is 1.49, New Zealand's is 1.62, Australia and America's both come in at 1.64, and Ireland's is 1.76.

On the flip side, impoverished developing nations where women have extremely limited access to education, healthcare, and contraception are recording the highest fertility rates.

Chad is number one, with a rate of 6.99 in 2021, while Niger is a close second (6.97), and Somalia (6.54) third. In fact, Sub-Saharan Africa will account for half of global births by 2100, with some countries in the region experiencing a baby boom rather than a bust, according to The Lancet.

In theory, this should put these poorer countries in a better position to negotiate fairer migration policies with richer nations, which may be crying out for young foreign talent as their working-age populations start to diminish.

The major study was led by the Institute for Health Metrics and Evaluation (IHME), which is located at the University of Washington and funded by the Bill & Melinda Gates Foundation.

Other findings from the report include the revelation that pro-natal policies like free childcare, extended parental leave, and family tax credits are doing little to encourage women in developed countries to have more kids.

The study's authors have also raised concerns that some countries could introduce Handmaid's Tale-style "draconian measures" to limit reproductive rights, such as restricting access to contraceptives and abortions.

The authors of the study suggest that the great baby bust is set to lead to "staggering" social and economic changes, transforming the way we live. In fact, it will "completely reconfigure the global economy and the international balance of power – and will necessitate reorganising societies", according to Natalia Bhattacharjee, co-lead author of the study and lead research scientist at IHME (as quoted in the Financial Times). 

Countries may struggle to care and pay for their elderly populations, with fewer working-age taxpayers available to finance senior healthcare and social security. (However, lower spending on education may offset this somewhat.)

Business activity could decline significantly. Pronounced labour shortages will likely plague most developed nations, and there'll also be fewer consumers to drive growth.

With the number of buyers ever decreasing, house prices could end up collapsing. Recessions may be an all-too-familiar occurrence as economies contract and, if fiscal activity is muted, the stock market will likely follow suit, leading to diminishing returns.

Falling fertility rates may also lead to tanking investment in entrepreneurial innovation as investors hedge against decreasing consumer demand, according to an article economist Katica Roy wrote for Fast Company in 2021.

However, the baby bust isn't all doom and gloom. In fact, falling fertility rates have long been seen as a sign of women's empowerment and are arguably very positive.

Declining fertility rates may result in striking benefits for the environment and higher wages given the smaller pool of workers. Housing is likely to become cheaper as demand falls (though a substantial market correction would be painful), and there should also be less pressure on public services and infrastructure.

In any case, technology may end up coming to the rescue. Artificial intelligence (AI) and advanced robots could lessen the impact of declining workforces by replacing vanishing human workers, according to Dr Christopher Murray, a lead author of the study published in The Lancet. 

Plus, medical advances and improving lifestyles could mean that older people stay healthier and capable of working for longer, taking the pressure off healthcare systems and younger taxpayers.

Mass immigration from the baby boom countries of Sub-Saharan Africa to more demographically challenged developed nations would have mutual benefits for the nations involved and help moderate the effects of the great baby bust.

Yet a slew of countries, particularly those with right-wing populist governments, have pushed back against immigration in recent years, with some evidence suggesting that societies become less welcoming to migrants as they age.

A 2020 UN report revealed that by then, two-thirds of European countries had introduced measures to boost fertility rates.

Numerous other nations, from South Korea to Canada, have pro-natalist policies in place, though as we've mentioned, the study has found their effect is relatively minimal.

They range from cash "baby bonuses" and tax breaks to free or subsidised childcare and extended parental leave. Countries are even resorting to state-sponsored dating, exemption from military service for fathers, marriage-guidance counselling, and patriotic campaigns that urge couples to procreate for the good of the motherland.

With all that in mind, let's examine 20 key nations to discover what they're doing to tackle the great baby bust.

Officially a national crisis, South Korea's fertility rate is the lowest in the world at 0.82. The rate is expected to stay at that level through to 2100, although the population is forecast to halve by that time.

The country's former two-child policy (which ended in 2021), a lack of rights for women in the workplace, and the exorbitant cost of raising a child in the nation have all been cited as the root causes behind South Korea's baby bust.

Since 2006, the government has spent more than $270 billion (£218bn) on trying to address the problem, with limited success. Initiatives and proposals have included subsidised daycare, cheap overseas household help, and exemption from military service for young fathers with three kids or more.

At 0.98, Taiwan's fertility rate is almost as low as South Korea's. It's predicted to slump to 0.90 by 2050, a rate it's expected to maintain into the next century.

The country's low fertility rate can be attributed to various factors, including past campaigns that sought to limit families to two children, the high cost of housing, low marriage rates, and even anxiety over the possibility of a Chinese invasion.

Again, governmental efforts to address the issue such as expanded parental leave, tax breaks, and childcare subsidies have all proven unsuccessful.

Singapore's fertility rate stands at 1.20. That figure is forecast to fall to 1.15 by the middle of the century and slide to 1.12 by 2100.

Among other things, government minister Indranee Rajah blames worries over the cost of raising children and pressure to be an excellent parent for the nation's paucity of births.

Erstwhile policies that have disincentivised large families have also contributed to the city-state's low fertility rate. Government initiatives to reverse the decline have included cash bonuses for new mothers, extended parental leave, and even a rap that encouraged couples to "do their national duty" and procreate. These measures have so far failed to achieve the desired effect.

Italy's fertility rate is among the lowest in Europe at just 1.21 and births have hit an all-time low. The number is expected to decrease to 1.18 by 2050, falling further to 1.09 by 2100.

The lack of stable jobs coupled with the high cost of raising a child is at the heart of Italy's fertility crisis, with Italian mothers among the oldest in Europe.

Recent governments have introduced several financial incentives, including a monthly child benefit, yet these measures are falling short and births continue to tumble in the country. Compounding the problem further is the reluctance of the current right-wing populist government to expand immigration.

The fertility rate in China stands at 1.23. As is the case in Italy, births in the People's Republic have dropped to record lows. The fertility rate is forecast to fall to 1.14 by 2050, though it's predicted to pick up slightly to 1.16 by 2100.

Factors behind the slump include the high cost of living and a lack of support for working mothers. And of course, there's also the effect of China's infamous one-child policy, which was in place from 1979 to 2015 and limited most urban families to one child and the majority of rural families to two.

The government is desperately trying to stave off depopulation by plying couples with free IVF, cash incentives, tax breaks, and more, and is heavily promoting "traditional" families. But whether these initiatives will work is highly debatable...

Japan has the world's oldest population and a fertility rate of just 1.26. The number is expected to remain unchanged between now and 2050 but by 2100, it's predicted to slip to 1.21.

The Japanese government has acknowledged that the so-called "demographic timebomb" is the biggest problem the country faces. Its origins lie in the nation's falling marriage rate, steep cost of living, and poor work-life balance (among other factors).

It's doubtful if its endeavours will do the trick but the government is going all out to encourage births with cash benefits for parents, better childcare access, and even AI-powered state-sponsored matchmaking. Japan is also betting big on AI to help solve its worsening labour shortage problem.

Spain's fertility rate comes in at 1.26 and its birth rate is plunging to new lows. The rate of fertility in the country is poised to fall to 1.23 by 2050 and dip further to 1.11 by the end of this century.

A lack of affordable childcare, Spain's precarious jobs market, and ever-rising housing costs are among the key contributing factors. And while the government has taken some steps to deal with the problem, including increasing the amount of parental leave on offer, more wide-reaching action is still needed to address the underlying causes.

The fertility rate in Austria is 1.46. It's expected to drop to 1.42 by 2050 and 1.34 by 2100.

The Austrian state offers comparatively generous support to families in the form of a regular cash child benefit that includes a school start allowance, a childcare allowance, tax credits for parents, free school travel, and more. The low birth rate can be attributed to other factors, however, including regulations that make it difficult for single women to have children.

Canada's fertility rate also stands at 1.46 based on 2021 figures and recently hit an all-time low. By 2050, it's forecast to have fallen to 1.39, before sinking yet further to 1.32 by 2100.

Demographics expert Kate Choi puts the country's super-low fertility rate down to "affordability issues", particularly relating to housing, which is discouraging people from having kids (as revealed by Choi to the CTV News Channel earlier this year).

Successive governments have introduced pro-natalist policies, with Quebec particularly open-handed, although this still hasn't reversed the trend. Canada may have to focus its efforts instead on increasing immigration and boosting productivity with AI and other technologies.

Russia's rate of fertility is 1.48, and last year the country recorded its lowest number of newborns since World War II. The current ongoing war in Ukraine has exacerbated the decline, with the rate projected to fall to 1.33 by 2050 and 1.21 by 2100.

President Putin has called for Russian women to have at least eight children, although his regime's efforts to tackle the issue of low fertility have yielded few results in a society that has long been plagued by high living costs.

The raft of initiatives has included patriotic calls to reproduce, cash payments, free school meals, and the revival of the "Mother's Heroine" medal, which was originally introduced by Joseph Stalin after World War II for women who had 10 or more children. Alongside the award, Putin is also offering a $16,000 (£13,000) "prize" for women who reach double figures with their offspring. 

The fertility rate in the UK has hit a record low of 1.49. It's set to fall further to 1.38 by 2050 and dip to 1.30 by 2100.

Raising a child is expensive in Britain, with childcare particularly costly and pro-natalist policies relatively few and far between. Back in 2015, the Conservative government under then-Prime Minister David Cameron even put a cap on families claiming child benefit and welfare payments for families with three or more children. Meanwhile, the current Conservative government's plan to expand free childcare has been beset by problems.

Germany's fertility rate is 1.53. It's forecast to drop to 1.47 by 2050 and end the century at 1.40.

The country's flagging fertility rate can be attributed to a number of reasons, ranging from Germany's high living costs to the pressures felt by working mothers.

Still, the nation's projected figure for 2100 is one of the highest in Europe. This could have something to do with Germany's deep-pocketed parental benefits and willingness to accept immigrants, though public attitudes and official policy have hardened of late.

New Zealand's fertility rate is 1.62, which is a record low. By 2050, it's predicted to tumble further to 1.45, landing at 1.35 by 2100.

Living costs, notably the country's high house prices and rents, are partly to blame for the nation's low fertility rate.

To tackle the problem head-on, the New Zealand government recently launched Fertility Counts, a collaboration with the private sector and academia that will look at ways to boost births, including funding IVF, introducing baby bonuses and tax credits for parents, extending parental leave, and subsidising childcare.

Australia's fertility rate is higher than New Zealand's at 1.64 but it's set to match it by 2050, when it's projected to fall to 1.45. By 2100, Australia is expected to lag behind New Zealand with a fertility rate of just 1.32.

Reasons for Australia's low birth rate include anxieties over the cost of living and climate change. Pro-natal perks, which are nothing new for the nation, have proven unsuccessful. In 2004, a $2,000 (£1,500) baby bonus was introduced, with couples also urged by former treasurer Peter Costello to have "one [baby] for mum, one for dad, and one for the country".

Looking ahead, Australia will likely have to soften its tough immigration rules in order to keep its population up and the economy ticking over.

The US fertility rate is 1.64. By 2050, the number is set to drop to 1.52 and by 2100 it's projected to fall to 1.45.

Compared to other developed countries, the decline through to 2100 won't be quite as pronounced, perhaps thanks to America's general openness to immigration. The US is also at the vanguard of innovation, so the country will be better placed than most to mitigate the demographic timebomb with AI, advanced robotics, and other technologies.

The expense of raising children in America is often suggested as one of the fundamental causes of the falling rate, as is the lack of parental leave and other perks, though subsidised childcare and other benefits are available to low-income families.

France's fertility rate is on the high side for Europe at 1.75, though well below the replacement level nonetheless. It's expected to fall to 1.56 by 2050 and 1.43 by 2100.

For years, France has promoted policies that encourage women to have kids, including baby bonuses, extra-generous maternity leave, and free childcare, which may explain its relatively high fertility rate.

That said, President Macron called for a "demographic rearmament" earlier this year, with plans announced to reform parental leave and roll out free fertility tests for the over-25s.

Ireland has one of the highest fertility rates in Europe at 1.76, though this figure is set to fall to 1.54 by 2050 and end the century at 1.40.

The EU country offers an array of pro-family benefits, including comparatively generous parental leave, child benefit payments, and free childcare, but, according to The Lancet study, even these incentives won't be enough to prevent the downward spiral of its fertility rate.

Like other countries, Ireland will likely have to expand immigration further to ease the worst effects of the declining rate.

The UAE's fertility rate stands at 1.90. It's forecast to drop to 1.53 by 2050 and carry on falling to 1.31 by 2100.

Better access to education for women, the high cost of raising children, and late marriages are among the reasons the rate is dropping. The UAE government has put in place incentives to encourage couples to have kids, such as marriage and housing benefits, baby bonuses, free education, and complementary healthcare, although these measures have had no marked effect so far.

India is predicted to experience one of the most drastic fertility rate drops, with the figure expected to fall from 1.91 to 1.29 by 2050 and end the century at 1.04, which would be among the lowest rates in the world. By contrast, the rate was as high as 6.18 in 1950.

The plummeting birth rate can be attributed to a range of factors, including higher rates of education among females, later marriages, and better access to contraception as the country has become more affluent.

Another important factor is the country's mass sterilisation programmes, with a BBC report in 2014 suggesting that four million operations were carried out between 2013 and 2014 alone.

In fact, government policies have seemingly been more focused on stopping rather than encouraging people from having lots of kids. India's future economy could take a painful hit as a consequence of its falling fertility rate, with the country also potentially having to contend with pronounced social imbalances due to a widespread preference for male children.

At 2.07, South Africa's fertility rate is almost at replacement level. But the number is projected to slip to 1.69 by 2050 and drop further to 1.45 by 2100, in stark contrast to the rest of Sub-Saharan Africa, where rates are expected to remain high.

Fertility rates are falling in South Africa for much the same reasons they're declining elsewhere: improved educational access for women, better availability of contraception, delayed marriage, and the mounting cost of raising a child.

Pro-natalist incentives do exist, such as the Child Support Grant, but they're more about alleviating poverty than boosting the fertility rate. South Africa will likely have to address the issue in a far more meaningful way as the century progresses.

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