Nearly half of all UK families have only one child, according to new official figures. 
The number of one-child families has increased by almost 700,000 in 15 years, and they are likely to be in the majority within a decade, the data suggests.
The Office for National Statistics (ONS) said larger families are under pressure because of “the greater challenge of combining work with childcare with three or more children compared with one or two,” the Daily Mail reports.
Many families feel they can no longer afford to have more than a single baby, experts said.
Most mothers are now in the workforce and those who stay at home to bring up their children are increasingly penalised by the tax and benefit system.
When the ONS Labour Force Survey started asking about the size of families in 1996, there were just over three million with a mother, father and one child – around 42 per cent of all families with children.
Last year there were 3.7 million families with just one child, or 47 per cent of all families with children.
The survey found there are now three million families with two children, roughly the same as in the mid-1990s.
But as a share of all families, two-child households had fallen from 41 per cent to 39 per cent.
The biggest decline came among families with three or more children.
There were more than 1.3 million such families in 1996, but only 1.1 million in 2012. They formed 14 per cent of all families with children, compared with 17 per cent in 1996.
The number of big families has remained relatively high largely because of the impact of Pakistani and Bangladeshi migrants, among whom there is less expectation that mothers should work and bigger families are more common.
The authoritative survey, based on a sample of 130,000 people across Britain, found parents with large families are more likely to live on state benefits than those with smaller ones.
Only five per cent of couples with one or two children are workless, the report said, but 13 per cent of those with three or more are dependent on benefits.
“Families with one or two dependent children are more likely to have at least one employed parent than those with three or more dependent children,” the report said.
