Contents

The outer edge

East Asia

Ultra-low fertility shows how yesterday's missing births narrow today's recovery

South Korea’s period total fertility rate (TFR) was 0.75 births per woman in 2024. The number is so far below replacement that even its meaning can be hard to feel. It describes one year’s childbearing pattern, not a permanent national fate, but years near that level have already made the youngest cohorts far smaller than the generations ahead of them.

The 2024 result was an improvement. The period TFR rose from 0.72 in 2023, and the annual birth count increased for the first time in nine years. That is genuinely encouraging. It also shows why a rate and a count must be read together: a recovery now works through a smaller number of potential parents than the country had before the long decline.

South Korea population pyramid, mid-2024

A narrow base before the outcome is settled South Korea’s population by age and sex in 2024. The small cohorts near the base will shape the number of potential parents a generation later. via Wikimedia Commons

Japan reached this stage earlier. Its population fell by 550,000 in the year ending October 2024, the fourteenth consecutive annual decline. After decades of low fertility, numerous older cohorts now produce more deaths while smaller younger cohorts produce fewer births.

China brings the same turn to a different scale and history. The one-child policy accelerated fertility decline through coercion and left injuries that cannot be reduced to a population chart. Ending the policy did not restore large families. In 2024, mainland China recorded 9.54 million births and 10.93 million deaths; its population fell by 1.39 million even though births rose from the previous year.

Recent UN estimates place Hong Kong and Taiwan near the lowest fertility levels in the world. Singapore’s resident period TFR was 0.97 in 2024 after decades of family policy. Different governments and histories have reached the same outer range, making any simple explanation harder to sustain.

The range of near-term outcomes narrows

Policy can help today’s adults marry or have the children they want. It cannot create the adults who would be forming families now if more children had been born twenty-five years ago.

Low fertility first changes the maternity ward. A generation later, it changes how many people can enter it as parents. East Asia shows the outer edge of that narrowing before the next section explains the mechanism: negative momentum.

Citations

  1. Statistics Korea, Birth Statistics in 2024, 2025.
  2. Statistics Bureau of Japan, Current Population Estimates as of October 1, 2024, 2025.
  3. National Bureau of Statistics of China, Statistical Communiqué of the People’s Republic of China on the 2024 National Economic and Social Development, 2025.
  4. Singapore Department of Statistics, “Births and Fertility—Latest Data”, 2025.
  5. United Nations, Department of Economic and Social Affairs, Population Division, World Population Prospects 2024: Summary of Results, 2024.