A study by the Marriage Foundation calculates that cohabiting couples who have children are more than twice as likely to split up as those who had tied the knot beforehand.
But of those who do not then go on to get married after having children, only a handful will still be together by the time the child is 16, it claims.
And it predicts that half of children born today will have been through a family break-up by the time they are 16.
The foundation, set up by the High Court judge Sir Paul Coleridge, said that the findings show that the idea of being “happily unmarried” is a myth.
And it accused the Government of being fixated with trying to “airbrush” the importance of traditional marriage out of discussion about family break-up, with an emphasis on “long term stable relationships” instead.The report, which analyses figures from the Office for National Statistics, found that 93 per cent of couples whose relationships are still intact by the time their child is a teenager are married.
It calculated that out of a typical group of 100 16-year-olds, 45 of them would have experienced a family split, while 55 would still be living with both parents.
But only four of the 100 teenagers would have unmarried parents who are still together by the time they are 16.
It compares the findings with those from the 2001 census and calculates that the likelihood of married and couples breaking up is largely unchanged in the last decade.
But because fewer couples now get married family break-up has nevertheless become more common, it concludes.
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