There are over eight billion people in the world - that's roughly 1600 times the number of people in New Zealand - yet around the globe alarm bells are ringing we are not reproducing enough.
There are concerns not enough babies are being born to replace the existing population. By the end of the century, the United Nations predicts 23 countries will see their populations halved.
It has governments scrambling to engineer a baby boom.
Weird and wacky ways to bring back what was once feared as a "population bomb" have surfaced with an AI version of Tinder, a sex minister appointed in Europe and many, many 'baby bonuses'.
Last month, National Party leader Christopher Luxon joked Kiwis, if they wish, should "go out there and have more babies".
While he was joking, he may have a point.
Distinguished Professor Emeritus Paul Spoonley said New Zealand has experienced one of the most rapid transitions from replacement-level fertility to well below of any high-income country.
In 2012, the country was still at replacement fertility sitting at 2.1 births per woman, but by 2017, New Zealand had sharply dropped well below and has sat at about 1.6 births per woman since.
"There are not enough births to replace the existing population," Spoonley told Newshub.
"The question is whether the country will become a 'low, low fertility' country (1.5 births or below) and my expectation is that it will over this decade. Others think not but we really do not know."
The fertility rate shows the average number of babies women would have in their life. The replacement rate in New Zealand is 2.1, which is the number of children a pair would have to have in order to replace themselves. In countries with high infant and child mortality rates, the replacement level is much higher.
The latest Stats NZ data shows in 2022, New Zealand's fertility rate was 1.66 births. It was slightly higher than the two previous years (1.64 and 1.61, respectively) but that was largely reflected in slower growth in the population of women aged 15 to 49 years.
Prof Spoonley said the main reasons for having fewer children such as the "one and done" notion, or none at all, are better educational outcomes for women, more women in jobs and the costs of living.
While these are great outcomes for women, declining populations can create problems. The most common fears are a shrinking workforce and an aging society.
However, works to reverse the population decline have proved largely unsuccessful.
What overseas countries are doing?
Fears of slowing populations are not new, with countries taking good, bad and down-right weird action to make the population arrow tick upwards.
People are so concerned about the population plummeting in Spain that they have appointed a 'sex minister' whose job is to get people busy between the sheets.
Head to the south of Europe and Sweden proposed an hour of paid sex leave each week in 2017, it wasn't brought in but the country was keen to reverse its falling reproduction rate.
But if you can't find a match to procreate with Japan has got you covered. Its government is funding artificial intelligence matchmaking schemes to help single residents find love.
For some countries, including our neighbours across the ditch, "baby bonuses" were introduced - providing people with cash for having another addition to the family.
Policies around the globe have historically targeted women or aimed to give a financial boost in a world where the cost of having children is ever-increasing.
But women should not be carrying the weight of the looming population crisis on their shoulders - as they say 'it takes two to tango'.
Policies aimed at men such as increased parental leave for dads have also been introduced overseas, with South Korea even vowing to exempt men who have three or more children by the age of 30 from compulsory military conscription.
Meanwhile, authoritarian governments have been resorting to often coercive policies by taking away the rights of women.
Overseas the 'population anxiety' has become a rationale for denying the rights of bodily autonomy to women and girls.
In Iran, access to abortions and vasectomies was restricted and the public health care system was banned from free distribution of contraceptives in an attempt to revive flagging population growth.
Romania banned access to abortion and contraception between 1966 and 1989 to boost the country's population. It worked in the short term but then birthrates quickly fell after women found ways around the ban. During that period, maternal mortality doubled.
In China, which has recently dropped to the second most populous country (behind India) in the world, according to the United Nations, abortions are being discouraged to try and boost births.
China essentially shot itself in the foot when it introduced its one-child policy in 1979. While the policy, which ended in 2016, had significant implications such as forced sterilizations, abortions and infanticide it also lead to the world's once most populous country recording negative population growth in 2022.
After realising China's one-kid-rule has been slowing down population growth over the past decade the Asian superpower has made multiple policy changes to try and create a baby boom such as tax deductions, longer maternity leave, improved maternal healthcare and housing subsidies.
But according to current United Nations projections, China's population is likely to drop below 1 billion by 2080.
For the rest of the world, efforts are mainly falling short as the UN said the global population growth rate peaked in the 1960s and has been falling ever since.
Gender equality first
Forget declining fertility and focus on gender equality first - the message from a 2023 report by the United Nations.
It found policies to influence people, especially women, to have more children aren't really working.
And Prof Spoonley agrees.
"As a generalisation, pro-natal policies have simply not worked," he said.
"What is interesting is how helpless pro-natal policies have been at reversing this fertility decline."
Prof Spoonley said one of the very few countries to have had an effect on fertility decline has been Sweden which increased fertility from 1.5 in 1998 to 2.0 in 2010, essentially by providing extensive support for those having babies.
"There are very significant maternal and paternal benefits and state care to encourage what is called a 'speed premium' (having several children in quick succession). Swedish policies are generally described as very 'women friendly'," he said.
But he noted the baby boost did not last and Sweeden's fertility rate, as of 2020, was 1.6.
The UN report found countries that have offered financial incentives to encourage women to have children haven't seen great results, however, it supports the policies such as parental leave for men and women and child tax credits.
Instead, it found migration is part of the solution and will drive population growth in rich countries.
Migration can generate significant benefits for migrants, their families and countries of origin, it said.
"Women and girls, in particular, see their bodies repeatedly invoked as the problem and solution to 'overpopulation'," the report said.
"Interventions aimed at influencing fertility rates, whether high or low, are never the answer because these rates are neither inherently good nor bad. With the right approach, resilient societies can thrive, whatever their fertility rate may be."
But what about those who want babies but can't?
Some countries overseas have opted to fully fund fertility treatment for those who want children but are having trouble conceiving.
Professor Greg Anderson, of the Centre for Neuroendocrinology at the University of Otago, told Newshub there needs to be more access for Kiwis to fertility treatment, as it is a large barrier for many couples.
He said about 10 percent of New Zealand women can't get pregnant when you define infertility as not being able to get conceive after a year of trying with unprotected sex.
For couples, that number boosts to around 15 percent - that's a huge chunk of the population who may want a child but not be able to conceive.
Prof Anderson said there needs to be more awareness, especially around biological infertility such as conditions like polycystic ovary syndrome and endometriosis so people know when to seek help.
In New Zealand, eligibility for fertility treatment is based on a score that takes into account factors like age, weight and how long they have been trying to get pregnant.
Prof Anderson said the factor of how long a couple has been trying to get pregnant is a "double-edged sword" because while time increases the score, as couples are increasingly deciding to have children later it edges them closer to the ineligible age (39+ for women and 55+ for men).
In New Zealand, private fertility treatment is at least $10,000 on average and while, freezing eggs or embryos is always an option, Prof Anderson warned their success rate is not 100 percent.
"If the Government decided to double the funding for fertility treatment, probably the thing to do would be to tweak the score. We certainly need that," Prof Anderson said.
"There needs to be more access to fertility treatment because it is an enormous barrier for couples."
He said the score ideally could be tweaked to allow couples who have been trying for a baby for at least six months.
"There are much more doable things that we can do like increasing awareness of conditions like endometriosis and polycystic ovarian syndrome so that people can seek treatment for those things, Prof Anderson said.
"There are new and emerging treatments for those conditions but women need to be aware of them and know to seek treatment early."
He agreed that at a population level, a lot of New Zealand's low fertility rate comes down to people choosing not to have kids.
"I think even if we were to double the number of fertility treatments for women with biological infertility, it's still probably not going to do very much for New Zealand's national fertility rates," Prof Anderson said.
He said we need evermore encouragement of situations where women can have kids and still work in their jobs and look at why many New Zealanders can't afford children.
"Although that might sound like a bit of a grim picture, there actually is real hope for government funding to change those things," he said.
