EXACTLY HALF of men say they would forgive their girlfriends if they cheated on them – as long as they did so with another woman.

That’s according to new research carried out by the University of Texas, which found that less than a quarter of women would return the favour, if their boyfriends cheated on them with another man.

The research asked 718 college students to respond to questions which imagined them as being in long-term relationships, where their other halves cheated for one reason or another.

The results – as reported by Reuters – indicated that 50 per cent, or exactly half, of the students said they would be prepared to continue a long-term relationship with a girlfriend if she had had an experience with another woman.

22 per cent, meanwhile, were prepared to forgive her if she had been with another man.

Women, by comparison, turned out to have different feelings on forgiveness: while 28 per cent (about two-in-seven) would stay with a man who had cheated on them, only 21 per cent would stay with a man who had cheated with another man.

The study’s lead author, PhD candidate Jaime Confer, said the differing reactions of men and women were down to “a robust jealousy mechanism”, which was triggered by different types of fears.

In men, it was triggered by a challenge to their paternity, while in women it was more likely activated by a fear of abandonment.

Men were, he added, more likely to tolerate female-female cheating because it presented “an opportunity to mate with more than one woman simultaneously, satisfying men’s greater desire for more partners”.

A co-author added, however, that the same-sex cheating scenario was “very rare in reality”, and that when asked if similar situations had arisen in real life, “men were significantly more likely than women to have ended their actual relationships following a partner’s affair”.