The research reveals that women born in 1978 are expected to have an average of one child by the age of 31, while for those born in 1951 the average age was 26.

Women born in 2007 are expected to have an average of one child by the age of 35 while this is expected to increase further to age 36 for those born in 2025.

The average size of families is also decreasing with women born in 1978 having 1.95 children compared with 2.04 for those born in 1951.

This trend is expected to continue with women born in 2007 expected to have 1.52 children and those born in 2025 to have an average of 1.46 children.

The analysis follows ONS data in October 2024 which revealed that fertility rates had dropped to a record low of 1.44 children per woman.

There were 591,072 live births in England and Wales in 2023, the lowest number of births since 1977 (569,259).

Stillbirths fell to 591,072 live births in England and Wales in 2023, the lowest level since 1977 (569,259).

ONS's Kerry Gadsdon said: ‘This is the first time we have used analysis of past trends together with projected fertility patterns to explore fertility among a future generation of women. While these projections cannot be treated as forecasts, they can provide insight into how fertility and family sizes may change in the coming years.

‘Our findings suggest those born in 2025 will on average go on to have babies later in life and to have smaller families, than previous generations of women. This would be a continuation of the current trend that we see when comparing fertility among women born in 1978 and 2007. The reasons behind when and if women have children are very personal. This may be driven by a range of factors including financial pressures and the timing of other life events such as partnership formation and moving into your own home generally happening later.'