Though studies vary, the general consensus remains that approximately 60 per cent of men and over 45 per cent of women will cheat at some point in their marriage.
The reasons why people stray from their partners are varied: some enjoy the act of deception; others say they feel bored in their marriages, or their spouses do not offer enough sexual or emotional gratification.
According to research by the University of New Hampshire men are seven per cent more likely to cheat than women.
This, the researchers claim, is because men and women’s cost-benefit analysis of infidelity are different.
For women, the “biological and socioeconomic factors – men who are good candidates to father a child and who have the education and financial stability to provide for a family” are paramount when deciding whether or not to embark on an affair.
This is not the same for men, and the likelihood of engaging in an extra-marital affair increases with age.
For men, the peak age for cheating is 55 years old.
Women’s infidelity crowns ten years earlier at 45 years old. After those ages the likelihood of infidelity tends to decline.
Research into infidelity is, however changing.
A study published in the Journal of Sex and Marital Therapy found that one in five Americans have been in non-monogamous relationships, and a different research paper confirmed that "older adults in open relationships reported being happier, healthier and more sexuality active than the general population of similar age and relationship status".