How researchers explain alluring sway of a woman's hips

'Women at peak fertility cycles walk more seductively':

UK: It was never going to be the most onerous of scientific endeavours. When experts set out to examine the alluring sway of a woman's hips when she walks, a delighted and charming young male researcher was tasked with chatting up more than 100 young single women.

The unnamed researcher then secretly filmed them from behind using a camera in his buttonhole. The covert footage was viewed by two other men - who were asked to judge each wiggle on an attractiveness scale of one to five.

Their research revealed that women at the peak of their fertility cycles walk more slowly and seductively than those who are not.

This subtle change in behaviour is subconscious but has clear evolutionary benefits - as it makes a woman appear more attractive just at the time when she is most likely to fall pregnant, the research showed.

The girls were unaware of the nature of the study and were asked for a saliva sample to test for the presence of a hormone. Levels of the hormone indicated whether they were approaching the most fertile time of the month.

And the secret of the wiggle, well known for leaving men smitten when demonstrated by attractive women such as the singer Beyonce, was confirmed when the researcher compared the hormone test with the ratings from the judging panel.

Professor Nicolas Gueguen led the study at the behavioural sciences unit of the University of Bretagne-Sud in France.

And it is not the first time Prof Gueguen has studied the female form. His previous research has examined whether a woman's bust size affects her ability to hitchhike and whether a woman's hair colour affects her success as a charity worker.

He is currently studying whether women wear shoes with higher heels when they are fertile. Daily Mail