We found that merely sniffing negative-emotion–related odorless tears obtained from women donors, induced reductions in sexual appeal attributed by men to pictures of women’s faces. Moreover, after sniffing such tears, men experienced reduced self-rated sexual arousal, reduced physiological measures of arousal, and reduced levels of testosterone. Finally, functional magnetic resonance imaging revealed that sniffing women's tears selectively reduced activity in brain-substrates of sexual arousal in men.
Link -via io9 | Photo by Flickr user RishiB used under Creative Commons license
I guess this is also why women there are forced to wear Burqas there, to disable their weapons of male destruction.