World Population Day – 11 July 2025

Observed each year on 11 July, World Population Day in 2025 focuses on the theme ‘Empowering young people to create the families they want in a fair and hopeful world’. This year’s theme brings attention to declining fertility rates across the globe. While public discourse often centres on fears of population collapse, the primary concern is that many young people are unable to form the families they would like.

The recent United Nations Population Fund (UNFPA)’s State of World Population report highlights a widespread lack of reproductive agency, particularly among young people, many of whom cannot have the children they want. This year's World Population Day calls attention to this issue, focusing on the largest-ever generation of young people and the importance of ensuring they have the rights and resources to shape their futures. UN Secretary-General António Guterres urged: “Let us stand with young people and build a future where every person can shape their destiny in a world that is fair, peaceful and full of hope.”

Professor Jane Falkingham CBE, Director of the ESRC Centre for Population Change and Connecting Generations (CPC-CG), notes: "Fertility decline is not simply a matter of choice. It reflects economic uncertainty, unaffordable childcare, precarious housing, and a mismatch between fertility intentions and the means to realise them."

CPC-CG researchers have been studying fertility and family formation trends since the Centre’s inception in 2009. The latest findings reveal that while the UK’s total fertility rate (TFR) is falling, the desire to have children has remained relatively stable. In the UK, the two-child norm persists, yet young adults are delaying or foregoing parenthood due to economic insecurity and pessimism about the future. Nearly half of UK adults aged 18–29 report being uncertain or unlikely to have children. Fertility intentions are closely linked to income and perceived life stability, both of which vary significantly by region.

Speaking to the Financial Times, Professor Ann Berrington, CPC-CG fertility and family research lead, explained: “Whilst some individuals desire to remain child-free, the empirical evidence suggests that there are a significant number who want children, but are currently unable to have them.”

In an interview for the Telegraph, Professor Melinda Mills, CG Co-Director, highlighted the impact of inflexible employers, economic precarity, and high housing costs on declining EU birth rates. She pointed out that increased female labour market participation often clashes with the demands of unpaid childcare. Delaying parenthood into the 30s also reduces opportunities to meet one’s desired family size.

Fertility and family formation: Latest research findings

Research by CPC-CG Co-Director Professor Hill Kulu, with Dr Bernice Kuang, Professor Ann Berrington and Dr Sarah Christison, used census-linked administrative data to examine childbearing patterns in Great Britain from the 1990s to today.

“We wanted to understand not just whether people are having fewer children, but when they're having them and how family formation differs across our nations,” said Professor Kulu.

Their study found first-birth rates declined during the 1990s, recovered slightly in the early 2000s, then declined again. The main change was timing, with people starting childbearing later, not overall family size. Once families had a first child, the timing between subsequent births stayed consistent. However, second- and third-birth rates fell in the late 1990s and stabilised in the early 2000s. In Scotland, second and third births were less common than in England and Wales. The study found little impact from changes in education or ethnicity, although there were sharp drops in first births among women with lower educational attainment.

To understand these changing family formation intentions, CPC researchers are also running the ESRC-funded UK Generations and Gender Survey (GGS), led by Professors Brienna Perelli-Harris and Ann Berrington, with Dr Olga Maslovskaya and Dr Bernice Kuang at the University of Southampton. The first round of UK GGS survey responses revealed an increasing number of young adults intending not to have children at all. The data show that 15% of the Gen Z (18–24-year-olds) survey respondents definitely do not intend to have children. Among childless older millennials (36–41), one-third say they definitely won’t have children. Environmental concerns play a role for older millennials, but for Gen Z, it’s more complex: those more likely to want children are also more concerned about climate change.

“Whilst we found that environmental concerns are a factor for older millennials intending to remain childless, our study suggests this isn’t the case for Gen Z,” says Professor Perelli-Harris. “This may be because some younger people do not intend to have children for other reasons, or it could be that Gen Zers who would like to have children are more worried about the planet that their children will inherit.”

If people do decide to have children, childcare access and costs are also major considerations. Families in the lowest income brackets spend up to 30% of their income on childcare, compared to 10% for higher earners. The average spend is £560 per month, with one in four paying over £800. Lower-income families are also less likely to use childcare, showing clear affordability and access issues. “Our findings suggest a lack of affordability may be stopping low-income families from using childcare services, and at the same time preventing parents from working more hours,” said Dr Kuang.

Childcare also remains strongly gendered. GGS data show that while flexible working helps some fathers share care duties, it has little effect for mothers, who often take on more responsibility despite also working. “Fathers contribute to childcare,” said Dr Kuang, “but mothers , even those who work outside the home, are much more likely to handle the difficult jobs that get in the way of the working day.”

In a Financial Times article, Professor Berrington linked childbearing hesitation to such broader concerns: “You might have a job, but if you’re worried about losing it, or worried about inflation or worried about conflict in Ukraine, then you still might hesitate to have children.”

Professor Berrington has also been working with Dr Lydia Palumbo and Professor Peter Eibich to explore how economic insecurity affects relationship outcomes. Highlighting the importance of family policies that reflect economic realities and provide support for couples in unstable situations, their research has found that financial stability predicts relationship progression. Employed cohabiting couples who are saving are more likely to marry, while those facing financial hardship are more likely to separate or remain in limbo. Female breadwinner couples are especially vulnerable to separation.

Housing is another key factor shaping young people’s life choices. Research by Louis MacPherson and Dr Francesca Fiori finds more young people in Scotland now rely on the private rental sector due to limited access to social housing or homeownership. Austerity, the global financial crisis, and stricter social housing criteria have left many young people choosing between remaining in the parental home or renting privately. The latter is associated with greater instability and delayed family formation. Louis MacPherson comments: “The study highlights the need for more affordable housing and tighter private rental sector regulation, aligning with the Scottish Government’s ‘Housing to 2040’ and ‘Population Strategy’ which recognise the role of safe, good quality, and affordable housing to support young people’s residential independence and family formation.”

CG member Molly Broome, an economist at the Resolution Foundation, published a report that found that, despite modest gains in homeownership rates among younger millennials, young people today remain significantly less likely to own homes compared to previous generations, with ownership rates for 25–34-year-olds falling from a peak of 55% in 1990 to just 31% in 2022-23. Speaking on the findings of the Housing Hurdles report, she said:

“After decades of falling youth home ownership, Britain has finally turned a corner with the share of young homeowners growing consistently since the mid-2010s. However, poorer young people have largely missed out on this recovery, and the property divide among young millennials has widened as a result. Housing costs have also been falling recently, but the scale of the crisis means that housing stress remains rampant among young people – particularly among poorer families, Londoners and private renters. There is a still way long way to go before Britain can claim to have tackled its housing crisis, and the Government must ensure that people aren’t left behind in efforts to improve the outlook for young people.”

These are examples of just some of the CPC-CG research helping to shape policymaking at multiple levels on today’s UN World Population Day theme. Indeed, the United Nations Population Fund (UNFPA)’s State of World Population report references CPC research on intergenerational co-residence and transitions to parenthood, and Professor Falkingham recently contributed to a UK Parliament POSTnote on declining birthrates.

“Together, these CPC-CG studies offer a detailed picture of how economic, social and policy factors interact to shape family life in the UK and beyond,” Professor Falkingham concludes. “As the UN’s 2025 State of World Population report argues, empowering young people is not only about services. It is about providing a sense of hope, security, and fairness. If young adults are to have the families they desire, we must listen to them and address the barriers they face. CPC and CG research continues to provide the data and insight needed to shape those solutions.”

Find out more about our Fertility and family research projects.

Further reading

Scotland’s ‘generation rent’ (CPC-CG Policy Briefing 88)

Living in precarious partnerships (CPC-CG Policy Briefing 81)

Who uses childcare in the UK and how much does it cost? (CPC-CG Policy Briefing 73)

Intending to remain childless: Are concerns about climate change and overpopulation the cause? (CPC-CG Policy Briefing 72)

How do parents share childcare that interferes with paid work? Work arrangements, flexible working, and childcare (Journal of Marriage and Family)

Understanding fertility trends in Britain: Do fertility intentions differ across England, Wales and Scotland? (CPC-CG Working Paper 105)

Long-term fertility trends by birth order in Britain: Comparison between England & Wales and Scotland (Population Studies)

Living in precarious partnerships: Understanding how young men’s and women’s economic precariousness contribute to outcomes of first cohabitation (Population Studies)

Housing Hurdles report (Resolution Foundation)

The Real Fertility Crisis (UNFPA State of World Population 2025 report)

Impacts of birthrate decline (POSTnote Research Briefing)

How place-based inequalities affect family formation (Mapineq webinar)

One in five people do not expect to have as many children as they want (Financial Times)

Flexible hours ‘trap’ mothers into doing more parenting (The Times)

Population change in the UK and lessons for Labour’s five missions (CPC-CG Factsheet)

The changing inter-relationship between partnership dynamics and fertility trends in Europe and the United States: A review (Demographic Research)

Genetics and reproductive behaviour: A review (Human Evolutionary Demography)

Posted 11/07/2025 08:01