Fertile women smell sexy, say scientists

Question: how does a man know if a woman is at that most fertile stage of the month and likely to get pregnant if he has sex with her?

Answer: he has a good sniff of the T-shirt she wears in bed.

It might sound a bit bizarre but this is precisely what scientists asked a group of men to do in a study designed to establish what sort of odours women gave off when they ovulated.

And the results came back strongly: a man thinks a woman smells particularly pleasant, even sexier, during the fertile period of her menstrual cycle.

Perfume ban

The researchers, from the University of Texas, Austin, US, got 17 women to participate in the T-shirt study.

The women were asked to wear one shirt for three consecutive nights during the most fertile phase of their 28-day cycle, and another garment during their least fertile period.

None of the women were allowed to use perfumes, fragrant soaps or wash powders, eat spicy foods, engage in sexual activity or use the pill.

All the shirts were then numbered and handed to a group of 52 men, who had to rate the nightwear in terms of how intense, how pleasant and how sexy they found the smell of the garments.

The results were striking, say the researchers, who publish details of their work in the journal Proceedings of the Royal Society B.

Smell rating

The men found the T-shirts worn during the fertile phase of the month significantly preferable.

Given that a woman goes through immense hormonal changes during her menstrual cycle, it is probably not that surprising that her body odours change with the different phases, the team say.

The results also fit with other studies that have demonstrated some of the more subtle signals women can send out to indicate they are fertile.

It is known, for example, that a woman's skin will lighten slightly and her breasts will tend to become more symmetrical around the fertile period.

One research project even suggested that women wore more revealing clothes during this time of the month.