No effects of exposure to women's fertile window body scents on men's hormonal and psychological responses

Abstract

Do men respond to women's peri-ovulatory body odors in functional ways? Prior studies reported more positive changes in men's testosterone and cortisol after exposure to women's scents collected within the putative fertile window (i.e., cycle days when conception is possible) compared to comparison odors, and also psychological priming effects that were differentially larger in response to the fertile window odors. We tested replication of these patterns in a study with precise estimation of women's ovulatory timing. Both axillary and genital scent samples were collected from undergraduate women on six nights spaced five days apart. Here, we tested men's responses to a subset of these samples that were chosen strategically to represent three cycle regions from each of 28 women with confirmed ovulation: the follicular phase prior to the start of the fertile window, the fertile window, and the luteal phase. A final sample of 182 men were randomly assigned to each smell one scent sample or plain water. Saliva samples were collected before and after smelling to assess changes in testosterone and cortisol, and psychological measures of both sexual priming and social approach motivation were assessed after stimulus exposure. Planned comparisons of fertile window to other stimuli revealed no statistically significant effects for any dependent variable, in spite of sufficient power to detect effect sizes reported in prior studies. Our findings thus failed to replicate prior publications that showed potentially adaptive responses to women's ovulatory odors. Discussion addresses the implications of these findings for the broader question of concealed ovulation in humans.