China's Demographic Decline: A Boulder Rolling Downhill
As China's fertility rate plunges to roughly half the replacement level of 2.1, Beijing is urgently deploying pro-natalist policies to boost births. However, this demographic decline now resembles a boulder rolling downhill—extremely difficult to stop and even harder to reverse. With profound socioeconomic factors at play, achieving success appears steeply challenging.
The Stark Reality of Plummeting Births
China recently announced that births in 2025 plunged to 7.92 million, down from 9.54 million the previous year. This figure represents almost half of what was projected (14.33 million) when the one-child policy was repealed in 2016. In fact, China's current birth levels are comparable to those of 1738 CE, when the country's total population was only about 150 million.
Having finally acknowledged this grim demographic reality, Chinese authorities introduced new pro-natalist policies last year, expecting births to rebound. Yet the decline in China's fertility rate was inevitable, much like that boulder rolling down a hill. Even if it can be pushed back uphill, the process will not happen quickly or easily.
Structural Challenges in Marriage and Gender Ratios
The downward trend in marriages will be particularly difficult to reverse. The number of women aged 20-34, who account for 85% of Chinese births, is expected to drop dramatically from 105 million in 2025 to just 58 million by 2050. Compounding this challenge, China's marriage market suffers from a pronounced mismatch.
Decades of sex-selective abortion have created a severe shortage of women of childbearing age. Simultaneously, women's higher educational attainment has created what's known as the 'leftover women' phenomenon, with female students now outnumbering males in higher education. Whereas the male-to-female ratio among six-year-olds in 2010 was 119:100, by 2022 when this cohort entered college, the ratio in undergraduate admissions had shifted to just 59:100.
This imbalance creates a dual problem: more men are unable to find wives, while more women are likely to remain unmarried due to their preference for more highly educated husbands. These demographic shifts create fundamental barriers to increasing birth rates through policy alone.
Learning from Japan's Ineffective Response
China's current policies represent a scaled-down version of Japan's largely ineffective response to demographic decline. In Japan, fertility fell from 1.45 in 2015 (already far below the replacement rate of 2.1) to just 1.15 in 2024. With China facing even deeper structural demographic constraints, it's unsurprising that its fertility rate has already fallen below Japan's.
Japan's experience offers several cautionary lessons. The average age for men and women at first marriage is negatively correlated with fertility, as is the proportion of unmarried women aged 25-29. In China, the average age at first marriage rose significantly from 26 for men and 24 for women in 2010 to 29 and 28, respectively, by 2020. More concerning, the share of unmarried women aged 25-29 surged from 9% in 2000 to 33% in 2020 and reached 43% by 2023.
The Urban Density Dilemma
An ecological principle states that density inhibits growth—whether of bacteria, plants, animal populations, or humans. Across wards and cities in Tokyo, population density shows a negative correlation with fertility rates. This same pattern appears in London, New York, and Shanghai.
Built-up urban areas in the United States typically have 800-2,000 people per square kilometer. Tokyo averages about 6,000 per square kilometer. In China, the average reaches 8,900 per square kilometer, with many districts in first- and second-tier cities—where young people flock—often reaching 20,000-30,000 per square kilometer.
High population density drives up housing costs, while higher price-to-income ratios negatively affect fertility decisions. In recent years, declining fertility in Canada, the United States, and Europe has been partly driven by soaring housing prices. Since China's price-to-income ratio far exceeds Japan's, and its housing bubble is much larger, boosting fertility would require transforming cities to lower population density and housing costs—a process that could trigger financial instability or even economic collapse.
Economic Constraints and Policy Limitations
The Chinese government has introduced a "new quality productive forces" policy to offset the economic drag of aging. However, such pro-growth measures inevitably prolong education, which delays childbearing, increases the proportion of unmarried individuals, and further lowers fertility.
Japan's experience demonstrates there are no easy solutions. The country funded childbirth subsidies by raising its consumption tax, but the burden ultimately fell on households, reducing disposable income as a share of GDP from 62% in 1994 to 55% in 2024—a loss that subsidies can scarcely offset.
Similarly, Taiwan's fertility rate fell from 1.68 in 2000 to 0.72 in 2025, partly reflecting the decline in household disposable income from 67% of GDP to 55%. In mainland China, household disposable income already accounts for only 43% of GDP, making child-rearing even more economically challenging.
The Political Economy of Demographic Solutions
China's best option to increase fertility would be to raise its household income share, which would also boost consumption and absorb excess capacity. However, Beijing is unlikely to pursue such a paradigm shift because it could weaken state finances and power, potentially reshaping China's political landscape.
Moreover, even if China could afford to increase fertility through generous social benefits, the effects might not last. Such interventions risk weakening family structures and reducing male labor-force participation. After Nordic countries adopted similar policies, the proportion of children born out of wedlock surged to 50-70%, with taxpayers supporting the elderly. This collectivist model, reminiscent of China's Great Leap Forward that led to millions of famine deaths, appears unsustainable in the long term.
A Chain Only as Strong as Its Weakest Links
The strength of a chain is determined by its weakest link, and in China's demographic crisis, several links need strengthening simultaneously. Fertility can rise only if China addresses all interconnected factors: gender imbalances, urban density, housing affordability, income distribution, and cultural shifts around marriage and family.
One hopes that China can eventually set an example that addresses these challenges without violating human rights. The path forward requires acknowledging that demographic reversal involves more than policy adjustments—it demands fundamental socioeconomic transformations that may challenge existing power structures and economic models.
The author is a senior scientist at the University of Wisconsin, Madison, who spearheaded a movement against China's one-child policy.
