Men who are economically dependent on their wives are more likely to cheat in order to prove their masculinity, a new study suggests.

Researchers found that in an average year, there is about a 5 per cent chance that women who are completely economically dependent on their husbands will cheat, whereas there is about a 15 per cent chance that men who are entirely economically dependent on their wives will have an affair. "You would think that people would not want to 'bite the hand that feeds them' so to speak, but that is not what my research shows," said study author Christin l Munsch, an assistant professor of sociology at the University of Connecticut.

"Instead, the findings indicate people like feeling relatively equal in their relationships. People don't like to feel dependent on another person," Munsch said. Munsch found that economic dependency increases the likelihood of engaging in infidelity for both men and women, but there appears to be something that makes men who are not primary breadwinners even more prone to cheating compared to women who are not primary breadwinners.

"Extramarital sex allows men undergoing a masculinity threat - that is not being primary breadwinners, as is culturally expected - to engage in behaviour culturally associated with masculinity," Munsch said. "For men, especially young men, the dominant definition of masculinity is scripted in terms of sexual virility and conquest, particularly with respect to multiple sex partners.

"Thus, 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," she said. The study, which will be published in the American Sociological Review, relies on data from the 2001 through 2011 waves of the US National longitudinal Survey of Youth and considers more than 2,750 married people who range in age from 18 to 32-years-old.

Munsch found that for women, the more they "breadwin" - that is, the larger their percentage of the combined marital income - the less likely they are to cheat. Munsch noted that women are least likely to engage in infidelity when they make 100 per cent of a couples' total income. Munsch said that women who are the primary breadwinners in their marriages often minimise their achievements, defer to their spouses, and increase their housework.

"This emotional and physical work is designed to decrease interpersonal conflict and shore up their husbands' masculinity. It is also aimed at keeping potentially strained relationships intact," Munsch said. Among men, those who are completely economically dependent on their spouses are the most likely to cheat. As the money men make relative to their spouses increases, their odds of committing adultery decrease until their total contribution to the pooled income reaches 70 per cent. Men are least likely to cheat when they bring home 70 per cent of a couples' total income.