Young Danes want more children than current fertility trends suggest they will eventually have, according to a large study of adults aged between 20 and 28. Around eight in ten participants said they hoped to become parents, with most expecting to have two or three children, despite Denmark’s fertility rate falling to around 1.5 children per woman.
The study examined responses from 20,594 women and 11,526 men participating in the Danish National Birth Cohort (Bedre Sundhed i Generationer). It found that 81.1% of women and 79.9% of men wanted children.
Among participants who hoped to become parents, women wanted an average of 2.46 children, while men wanted 2.43. Only 7.8% of women and 8.7% of men said they did not want children, while just over 11% remained uncertain.
The findings were published in the Danish Medical Journal as part of BIOSFER, an EU-funded research project investigating the biological, social and psychological causes of declining fertility.
Denmark’s fertility gap begins with timing
The study points to a substantial fertility gap in Denmark: the difference between the number of children people would like to have and the number they are expected to have in practice.
Young women said they would prefer to have their first child at an average age of 27.3, while young men chose 28.4. They expected to have their final child at 32.9 and 34 respectively.
In reality, Danish parents are starting families considerably later. In 2025, the average age of first-time mothers was 30.4, compared with 28.1 in 2000. The average first-time father was 31.9, up from 30.6 at the beginning of the century.
Denmark’s total fertility rate stood at 1.506 children per woman in 2025, according to Statistics Denmark. This was far below both the preferences expressed by the study participants and the approximate replacement level of 2.1 children per woman.
“Something probably happens between the time we ask young people and the end of their reproductive years that will leave a gap between wishes and reality,” Cecilia Ramlau-Hansen, professor of epidemiology at Aarhus University’s Department of Public Health, told TV 2.
“What happens is what we need to investigate. The aim is to obtain knowledge that can help us understand which measures may increase the birth rate,” she added.
Researchers will examine barriers to parenthood
The study does not identify a single reason why young adults may end up having fewer children than planned.
Possible explanations include longer education, insecure employment, housing costs, difficulties finding a partner, economic uncertainty and concerns about climate change or international instability. Biological fertility may also decline as parenthood is postponed.
The researchers will now use data collected through the BIOSFER project to examine the barriers that emerge between people’s intentions in their twenties and their eventual family size.
The participants were born between 1996 and 2003 and have been followed since pregnancy through the Danish National Birth Cohort. Researchers therefore have access to information about their development, family background, health and exposure to environmental factors from before birth.
BIOSFER combines this Danish cohort with a corresponding Norwegian study. In total, the project can draw on data from more than 200,000 young adults in Denmark and Norway.
The research is supported by an approximately DKK 104 million grant (€13.9 million) from the European Research Council. Researchers from Aarhus University, the Norwegian Institute of Public Health and the Max Planck Institute for Demographic Research are involved.
Family policies have not reversed declining births
Denmark provides extensive parental leave, subsidised childcare and relatively favourable working conditions for parents. According to the OECD, the country spends a comparatively large share of its economy on family support, while 97% of children aged three to five attend full-time childcare.
These policies have not prevented fertility from declining. The OECD has noted that the reasons people delay or abandon plans for parenthood are complex and cannot be explained by public policy alone.
Economic and social differences also matter. Childlessness has increased particularly among people with lower levels of education and income. More than one-third of Danish men in the lowest educational group remain childless, according to the OECD.
Women may also face long-term professional costs after becoming parents. Danish mothers experience an earnings reduction of around 20% compared with otherwise similar men, despite Denmark’s high female employment rate and developed welfare system.
A Nordic challenge beyond Denmark
Falling fertility is not limited to Denmark. Birth rates have declined across the Nordic region, including in countries with extensive welfare systems, affordable childcare and generous parental leave.
The Danish study nevertheless suggests that declining fertility does not primarily reflect a broad rejection of parenthood among younger generations. Most participants still imagined a future with two or three children.
The central question for researchers and policymakers is therefore not simply why young people do not want children, but why so many are unable to realise the family lives they say they want. The next stages of the BIOSFER project are expected to provide more detailed evidence about when that gap develops and which social, economic or biological factors contribute to it.
