Why some men can’t stop themselves being unfaithful

FATHERHOOD CAN DIAL DOWN A MAN’S LIBIDO

FASCINATINGLY in the last trimester of the mother’s pregnancy, a father’s testosterone levels fall, before an extra dip after the birth.

This is part of a biological adaptation to ensure the dad will help care for his child. Testosterone can exacerbate physical aggression and increase libido — traits hardly ideal for new fathers.

Indeed, research shows men without young babies have less oxytocin — the ‘cuddle hormone’ — and more testosterone in their blood. Their brains are also quicker to react to sexual stimuli.

. . . BUT SOME ARE DRIVEN TO CHEAT

HOWEVER, not every new father is hormonally driven to fixate on the family. Men may also have a tendency for infidelity after having children, potentially because cheating causes the pleasure hormone dopamine to be released.

It’s interesting also to note that the stress hormone cortisol plays a role in seduction, with a different effect in men and women.

If you’re a woman with a high level of cortisol, you’re less receptive to seduction attempts, whereas stressed men are more open to these — perhaps through the prospect of lovemaking as a quick way to relieve stress.

HOW TO TELL WHEN YOU’RE MOST FERTILE

IT’S all in your kiss. Researchers have found that, due to the influence of oestrogen, women can send messages about their fertility via their saliva. Around the time of ovulation, for example, saliva contains more sugar, so a woman’s kisses literally taste sweeter at this time.