Since mothers from India, Poland and Pakistan give birth in record numbers, a quarter of all babies born in the UK are the children of immigrants.
Figures revealed that a record number of nearly 200,000 babies were born to immigrant mothers last year.
The children of women who were themselves born abroad made up nearly a quarter of all the babies born in Britain.
The figures showed that 24 percent of births in 2011 were to women who had not themselves been born in Britain, which is the best indicator statisticians have for who is an immigrant.
In London, where a high proportion of migrants choose to live, the share of births to foreign-born mothers was well over half, 57 percent.
The five countries from which the greatest numbers of foreign-born mothers came were Poland, Pakistan, India, Bangladesh and Nigeria.
The share of new babies born to migrant mothers has more than doubled in 20 years and continues to shoot up, the report said.
According to the ONS analysis, the number of babies born to British-born mothers barely changed in the five years from 2007 to 2011, up from 603,000 to 612,000.
However, migrant mother births went up from 169,000 to 196,000, an increase of 16 percent.
However, the report pointed out that 'many of those born in Germany will be British nationals whose parents were serving in the armed forces in Germany at the time of their birth'.