The Office for National Statistics is drawing on this research to set fertility assumptions for the National Population Projections.
As part of the Centre for Population Change, Southampton academics are analysing the continuing decline in UK fertility rates, its cause and likely consequences for future patterns of childbearing.
Led by Professor Ann Berrington, Professor of Demography and Social Statistics, the team has developed new fertility forecasting methods that incorporate parity into their statistical modelling.
Rather than just projecting overall birth rates, the models account for whether individuals are having a first, second or later child. This improves accuracy by recognising that the likelihood of further births often depends on how many children someone already has.
Falling fertility rates
Fertility rates in the UK have declined to historically low levels. They have fallen fastest among younger women and for first births. Second and third births have fallen more slowly among those who are already parents.
If recent (2023) rates continued into the future, the average number of children per woman would be 1.3 in Scotland, 1.4 in England and Wales and 1.7 in Northern Ireland.
Effective planning for schooling, housing, childcare services, and health and welfare provisions, requires understanding whether this drop reflects personal choice or structural barriers preventing individuals from achieving their preferred family size.
Reasons behind recent declines in fertility in the UK are multifaceted, but our analyses using data from the UK Generations and Gender Survey show that economic uncertainty and financial worries are key.
Professor Ann Berrington, Professor of Demography and Social Statistics, Centre for Population Change
Exploring the data behind the decline
Using census-linked data from the UK’s National Longitudinal Studies, Southampton researchers have been able to show that for those born in the 1990s and 2000s, childbearing at a younger age has been falling rapidly.
Evidence from the data reveals that it is individuals with lower educational qualifications who are seeing the steepest decline in first birth rates, suggesting that socio-economic constraints may be preventing younger individuals with fewer resources from starting a family.
These findings are supported by evidence from the UK Generations and Gender Survey, an internationally comparative study run for the first time in the UK by the Southampton team. Survey findings indicate that childless individuals with lower incomes and concerns for their future finances are less likely to become parents.
Results from the survey also reveal that, while desired family size remains about two children per person, individuals’ intentions of how many children they will actually have are much lower. Among Generation Z (aged 18 to 24), 15 percent of childless respondents said they definitely do not intend to have a child, a much higher proportion than the previous generation.
Using research findings to shape policy
The research findings demonstrate the need for policies that support individuals and couples in making their transition to adulthood, including starting a family.
A holistic approach is required, providing people with stable, reasonably paid employment and affordable housing so that they feel secure about their financial futures and supported to have the families they desire.
