Divorce can spread like a virus amongst friends, family and work places, according to new research.
Scientists suggest that if an immediate friend, family member or colleague goes through a marriage break-up, a person’s own chance of divorce increases by 75 per cent.
The domino effect means that even the marriage breakdown of a friend-of-a-friend could raise the chance of a person’s own marriage ending by a third.
Researchers have dubbed the effect “divorce clustering” and say that marriage break-ups within friendship groups cause couples to start questioning their own relationships.
A friend’s divorce can also reduce the social stigma of splitting up, even when children are involved, according to the American researchers.
The findings come from a continuing study into the lives of 12,000 Americans living in Framingham, New England since 1948.
The study was conducted by political science professor Rose McDermott, of Brown University, and social scientists James Fowler, of the University of California, and Nicholas Christakis, of Harvard.
Dr McDermott said: “These results go beyond previous work intimating a person-to-person effect to suggest a person-to-person-to-person effect”.
“Individuals who get divorced may influence not only their friends, but their friends’ friends as the propensity to divorce spreads”, she added.
She confirmed: “A person’s tendency to divorce depends not just on his friend’s divorce status, but also extends to his friend’s friend.
“The full network shows that participants are 75 per cent more likely to be divorced if a person – obviously other than their spouse – that they are directly connected to is divorced.
“The size of the effect for people at two degrees of separation, for example the friend of a friend, is 33 per cent. At three degrees the effect disappears.”
Researchers found that the divorce trend was not just among friends but also among family members and work colleagues.
In January former Tory leader, Iain Duncan Smith, warned that easy divorce sent out the message that marriage is “disposable”.
Mr Duncan Smith, who heads leading think-tank the Centre for Social Justice, said marriage leads to the “best outcomes for adults and children”.
Writing in the Independent, he said “family breakdown profoundly impacts both adults and children, leading to poorer mental and physical health and poorer life outcomes.”
He added: “Marriage, as the family form which leads to the best outcomes for adults and children, should be championed and supported.”
Last year a Government-commissioned report found that children whose parents separate are likely to suffer “enduring” problems with their education, mental health and future relationships.
Girls are often worst hit by the consequences of their parents’ separation later in life, experiencing more anxiety and depression as adults than their male counterparts, the report said.
In a separate survey of 1,600 under ten-year-olds, divorce topped the list of things they would ban first if they ruled the world.