Scent of a woman : Are body odours cues to potential female fertility?

Abstract

Background: Chemosensory communication is crucial for mediating a variety of social behaviours of both human and non-human species. Body odours transmit diverse information such as gender or reproductive status. Here we tested whether a woman's body odour acts as a chemosensory marker of her reproductive fitness by exploring the relationship between levels of reproductive hormones and women's body odour attractiveness.

Methods: Fifty-seven men rated body odours of 28 healthy, naturally cycling women of reproductive age. We collected all odours at peak fertility to control for menstrual cycle effects on body odour attractiveness. Women's salivary estradiol, progesterone, testosterone and cortisol levels were assessed at the time of odour collection to test whether hormone levels explain body odour attractiveness.

Results: We found that the men highly agreed on how attractive they found women's body odours (ICC = .983). Interestingly, women's body odour attractiveness was predicted by their estradiol (Estimate = 9.62, p = .003) and progesterone levels (Estimate = −10.83, p < .001): The higher a woman's levels of estradiol and the lower her levels of progesterone, the more attractive her body odour was rated.

Conclusion: Chemical communication of sex and reproductive stage are ubiquitous in the animal kingdom, facilitating sexual selection that arises through competition over mates. Our results provide strong evidence that humans also use chemical cues to communicate their reproductive potential. Since estradiol and progesterone levels can be seen as indices of reproductive health and fertility, we propose that body odours serve as reliable cues to women's reproductive fitness.