Think you’ve got good gaydar? Being able to tell if that cute guy is gay or straight has to do with whether you’re on your period.

But it only goes for working out whether a man is gay or not – a woman’s menstrual cycle doesn’t affect her ability to tell if another woman is a lesbian, a recent Canadian study found.

Peak ovulation
A woman’s gaydar is sharpest when she’s closest to the ovulation part of her menstrual cycle, the study of 40 heterosexual female students showed.

Students looked at photos of men and then guessed whether or not they were gay. Researchers recorded how close the women were to getting their period. They found that those 14 days into their cycles – the time of ‘peak ovulation’ when they were at their most fertile – had the best gaydar.

But when it came to being able to tell if women in photos were lesbians, the menstrual cycle made no difference. The link between fertility and gaydar is only true for detecting whether a guy is gay or not.

Most fertile
Women closest to ovulation have the most to gain from being able to tell if a guy is gay, according to researchers. That’s because when they’re most fertile they have all the more reason to find a straight partner to fertilise their egg.

It’s not just gaydar that’s affected by a woman’s menstrual cycle, other studies have shown. Women at their most fertile time categorise men’s faces more quickly than women’s. What’s more, they find rugged, square-jawed masculine features more attractive.

Partner up
Being able to tell if a guy is gay is affected by other factors besides the menstrual cycle, the Canadian study found. Women who read a romantic story before guessing if men in photos were gay had better gaydar than those who hadn’t been ‘primed’ for romance.

Whether it’s because a woman’s ready for romance or her body is ready to get pregnant, good gaydar is affected by a drive towards finding a partner, researchers concluded.

By Sarah Moses

Photo: aBbYhaLO under CC licence / argus / Love Matters

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