London - Four in ten children born in the year 2000 were not living with both parents by the age of 11.
And modern youngsters are four times as likely as those born in the 1960s to experience a family collapse, the study revealed.
Researchers blamed the spread of family breakdown on the ease of divorce and the lack of shame felt by couples who separate.
They said youngsters whose mother and father had broken up were far more likely to have behaviour problems.
The state-funded Millennium Cohort Survey of more than 13 000 children born around the year 2000 found unmarried parents were responsible for the most cases of family break-up.
At the age of 11, around 92 percent of children born to married couples were still living with both their mother and father.
For those with cohabiting parents, the proportion was only 55 percent. The analysis of the results by academics from the Institute of Education said: “Nearly four in every ten children born at the turn of the century lived through at least one change in their parents’ relationship status in their first 11 years - up from one in ten in 1969.”
For many youngsters, the anguish of seeing their mother and father separate is not just a one-off. The study said one in seven had been through more than one family break-up.
The fresh evidence of growing levels of family breakdown comes at a time of deepening concern over the decline of marriage and its impact on children.
Recent studies have underlined the probability that couples who marry will be educated and have good jobs. Those who cohabit are more likely to be poor, unemployed and have few qualifications. Dr Roxanne Connelly, the lead author of the report, said there is now less stigma surrounding divorce, meaning couples suffering relationship problems are more likely to split up.
“Some of these parents might have previously stayed together while living in misery,” she added. “But many might have worked harder on their marriages, instead of giving up more easily, if there was more of a stigma.”
The report compared the state of families today and in 1969, when a similar large-scale study was undertaken.
That was the year when major reforms ushered in the era of “quickie” divorces. Since then, successive governments have removed tax incentives for couples to marry.
Harry Benson of the Marriage Foundation think tank, launched by family judge Sir Paul Coleridge to urge couples to wed, said: “The message from this study should be obvious.
“If we’re not encouraging parents to get married, we’re increasing the risks for their children.” - Daily Mail