The surprising thing that makes your partner more likely to be unfaithful

Thought those with more economic power are more likely to be unfaithful? A new study has found this is not the case in younger couples.

The research, published in the American Sociological Review, found that millennial male and female bread-winners (snake people, if you will) are more likely to be cheated on.

'Her Support, His Support: Money, Masculinity, and Marital Infidelity' examined data from 2,750 heterosexual married couples aged between 18-32 years old collected by America's National Longitudinal Survey of Youth, which has been tracking individuals since 1997.

It found women out-earning their partners are even more likely to be cheated on: in one year there is a five per cent chance that economically dependent female spouses will cheat, while there is a 15 per cent chance economically dependent male spouses will cheat.

"Extramarital sex allows men undergoing a masculinity threat - that is not being primary breadwinners, as is culturally expected - to engage in behavior culturally associated with masculinity," sole author Christin Munsch said. "Engaging in infidelity may be a way of reestablishing threatened masculinity. Simultaneously, infidelity allows threatened men to distance themselves from, and perhaps punish, their higher earning spouses."

The men least likely to cheat were those bringing home 70 per cent of a couple's income - after that their chance of infidelity increases. Munsch says this is because these men believe their wives are totally dependent and won't leave them even if they cheat.

"What is surprising, though, is that this increase in the likelihood of men engaging in infidelity that occurs as they make significantly more than their wives is relatively small compared to the increase in the likelihood of cheating that takes place among men as they become more economically dependent," she added. "But, the affairs of economically dependent men simply don't garner media attention, so we hear about this kind of infidelity far less often."

Full study: Her Support, His Support: Money, Masculinity, and Marital Infidelity

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