Men from poor backgrounds are twice as likely to be single in middle age than those from rich families, research suggests.
Research by the Institute for Fiscal Studies (IFS) shows that the marriage prospects of men are linked to their upbringing, and that the disparity between those from well-off and poor families has widened in recent years, reflecting a reduction in social mobility.
The study found that more than a third of men aged 42 from the poorest fifth of families did not live with a partner in 2012. That compared with only a seventh from high-income backgrounds.
It added that men from disadvantaged backgrounds experienced lower rates of marriage and higher rates of divorce.
The IFS said it was "well known" that the sons of richer parents tended to go on to enjoy greater earning power.
But it also found that the partners of those from richer backgrounds earned 70% more than the partners of men from poorer families.
"Female earnings are an increasingly important component of household income and so these trends significantly reduce the household incomes of men who grew up in poor families compared with those of men who grew up in rich families," the IFS said.
It said the earnings gap with those from less well-off backgrounds was widening.
In 2012, employed 42-year-old men whose parents were among the richest fifth of households earned on average 88% more than those from the poorest families, it said. Back in 2000 the figure was only 47%.
Just about managing
It added that men from poorer backgrounds were twice as likely to be out of work as those from richer backgrounds.
The IFS based its findings on the most recent long-term study available, which surveyed people born in 1970 and followed them over time.
Chris Belfield, a research economist at the IFS, said: "Focusing solely on the earnings of men in work understates the importance of family background in determining living standards.
"As well as having higher earnings, those from richer families are more likely to be in work, more likely to have a partner and more likely to have a higher-earning partner than those from less well-off backgrounds. And all these inequalities have been widening over time."
Prime Minister Theresa May has promised to "build an economy that works for everyone" and do more for families who are "just about managing" since coming to power last July.
A Treasury spokesman added that overall, income inequality had actually fallen and that more people were currently in work than ever before.