Last year just 260,000 children were born. In 1970, that figure was one million.
'Age quake' concerns
It has stoked concerns of an "age quake", a phenomenon where a country that has more older people and fewer younger people to support them could lead to economic and social crises.
The term was coined by British author and demographer Paul Wallace in 1999. Korea was called out then as a nation that could experience an age quake earlier than others due to its disastrous demographics.
An ageing population means there are higher healthcare and other costs but fewer younger people to fill tax coffers to fund that spending. It also means the country could have a shortage of workers.
By 2026, the elderly could make up 20 per cent of Korea's entire population. The working population could drop by a third over the next three decades.
A tough employment market, unequal pay, the high cost of living and raising children, and a difficulty in getting back into well-paid work after having kids have all been cited as factors in Korea's extraordinarily low birth rate.
Employers are said to be too focused on employing younger people rather than giving opportunities to older Koreans.
Also, in many cases, women are still expected to look after the home and children rather than it being a shared task.
Many women are now putting off having children until they feel they have an established career.
The average age women give birth in South Korea is creeping up, from 33.1 in 2020 to 33.4 in 2022.
Indeed, the fertility rate for women above 35 years of age has risen and the rate for women in their early 40s is the highest ever, showing people are delaying starting a family.
In 2021, the interior ministry in Seoul called for "fundamental changes" to balance the country's demographics.
Koreans now receive a baby bonus of 2 million won ($2407) as well as 300,000 won ($361) every month for the first year of the child's life.
Countries with highest – and lowest – birthrates
The country with the second-lowest fertility rate in the Organisation for Economic Co-operation and Development (OECD) countries – a grouping of mostly developed nations – is Italy.
Its fertility rate of 1.2 births per woman is far above South Korea – but still some way below the ideal of 2.1 births.
Australia's fertility rate is 1.58, having fallen from 1.79 in 2016. That's the country's lowest birthrate for a decade.
Countries close to or above the 2.1 rate include Mexico, Peru, South Africa, Saudi Arabia and Indonesia.
A number of African countries – including Niger and Angola – have the world's highest birthrates.
While Israel's fertility rate is dropping, it nonetheless has one of the world's leading fertility rates among developed nations with on average 2.9 children per woman.