More than a quarter of births were to mothers who were born outside the UK last year, new figures revealed today.
They accounted for a record 28.4 per cent of the total live births – up from just 11.6 per cent in 1990.
Meanwhile, the trend for women waiting until they are older to have children has continued.
Fertility rates decreased in every age group apart from the over-40s in 2017, according to the Office for National Statistics (ONS).
There are now 16.1 births per 1,000 women in that band – up 1.3 per cent year on year and the highest level since the post-war baby boom.
Official figures show foreign-born mothers accounted for a record 28.4 per cent of the total live births last year – up from just 11.6 per cent in 1990
The picture emerged in the latest figures for births released by the statistics body.
There were 679,106 live births in England and Wales in 2017, a decrease of 2.5 per cent from 2016 and the lowest number since 2006, the figures show.
Nearly three in 10 (28.4 per cent) births were to mothers born outside the UK, up from 28.2 per cent last year and rising for the 27th consecutive year.
Fertility rates decreased for every age group apart from women over 40, where there was a 1.3 per cet increase from 2016.
The rate – 16.1 births per 1,000 women in that age group – is the highest since 1949.
For the third consecutive year, and the third time since 1947, the fertility rate for women over 40 exceeded the rate for women under 20.
The average age of mothers has increased from 26.4 in 1975 to 30.5 in 2017, the ONS said.
Meanwhile, the number of stillbirths in England and Wales has fallen to a record low.
There were 2,873 stillborn babies in 2017 compared with 3,112 in 2016, a decrease of 7.7 per cent.
That is the lowest number since records began in 1927, the ONS said.
The rate decreased from 4.4 per 1,000 births in 2016 to 4.2 in 2017, the lowest in 90 years.
For the third consecutive year, the fertility rate – births per thousand women – for over 40s was higher than that for under 20s
Since 2007, the rate has fallen by 19.2 per cent.
In 1927, there were 26,021 babies stillborn and 38.3 per 1,000 births.
ONS spokeswoman Nicola Haines said: “Birth rates for live births have decreased for all women except those aged 40 years and over where the birth rate has continued to rise, following a trend seen for the last 40 years.
“Despite this, the proportion of women aged 40 and over having a baby still remains below that seen in the 1940s.”
She added: “The stillbirth rate has dropped to a record low, declining each year since 2011.
“It is a step towards achieving a government ambition to reduce the rate of stillbirths by introducing new maternity strategies while ensuring the best and safest care.”