Cheating on your wife is bad for your health as well as your marriage, according to a recent study.
The findings were made by Italian researchers at the University of Florence who reviewed previous studies on infidelity and its effects.
They said ‘sudden coital death’ was much more common when a man was meeting his mistress than when he was with his wife, the Daily Mail reported.
Studies also showed that most men who died during sex were having an affair and meeting away from the family home.
Furred-up arteries were blamed for more than a third of male deaths during sex - as the physical demands of sex is said to cause the fatty plaque that has built up inside arteries to rupture.
Heart attacks were the next biggest cause of death, with researchers suggesting the stress of wining, dining and satisfying a younger woman, and the stress of keeping it a secret, were to blame.
Researcher Dr Alessandra Fisher said extra-marital sex could be more stressful because the lover is often younger than the wife and the sex tends to follow more excessive drinking and/or eating.
"It is possible that a secret sexual encounter in an unfamiliar setting may significantly increase blood pressure and heart rate, leading to increased oxygen demand," Dr Fisher said.
Guilt may also play a role with some research suggesting heart problems are more common among cheats who are still attracted to their wife.
"Betraying this partner could punish him," she said.
The overview also suggests that in any one year, four per cent of married men will have an affair.
Over the course of a man's life, there is a 50-50 chance of him straying.