Preliminary evidence of olfactory signals of women's fertility increasing social avoidance behavior towards women in pair-bonded men.

Previous studies suggest that women's body odor is perceived as more attractive during ovulation and that exposure to women's chemical signals of high fertility leads to increased mating motivation. Given that pair-bonded men react differently than single men to unfamiliar women, we investigated whether women's chemical signals of fertility influence approach behavior among pair-bonded and single men. In the first experiment, men performed the Comfortable Interpersonal Distance task while exposed to body odor samples from women who were ovulating and from the same women during their luteal phase. We found that in the presence of the body odor from ovulation, pair-bonded, but not single men, maintained greater distance from different protagonists, particularly from women. In a second experiment we exposed men to women's body odors while they rated the attractiveness and beauty of women's faces. Although the ratings of women's beauty did not differ across odor conditions, when the pair-bonded men were exposed to the high fertility odor they rated highly attractive women as less sexually attractive. The results suggest that exposure to fertility cues from unfamiliar women may trigger social avoidance in pair-bonded men, an outcome that may result from identifying such cues as threats to their relationship.