Unlike men, women’s genital arousal is category-nonspecific with respect to sexual orientation, such that their genital responses do not differentiate stimuli by gender. A possible explanation for women’s nonspecific sexual response is the inclusion of women at different phases of the menstrual cycle or women using hormonal contraceptives in sexual psychophysiology research, which may be obscuring a specificity effect. The present study employs the ovulatory-shift hypothesis – used to explain a shift in women’s preferences for masculine traits during peak fertility – as an explanatory model for women’s nonspecific sexual arousal. Twenty-nine naturally-cycling women were tested at two points in their menstrual cycles (follicular and luteal) to determine the role of hormonal variation, as estimated by fertility status, on the specificity of genital (using vaginal photoplethysmograph) and subjective sexual arousal. Cycle phase at the time of first testing was counterbalanced; however, no effect of order was observed. Inconsistent with the ovulatory-shift model, the predicted mid-cycle shift in preferences for masculinity or sexual activity at peak fertility was not obtained. Category-specificity of genital arousal did not increase during the follicular phase. A statistical trend was observed for higher genital arousal to couple sex stimuli during the follicular phase compared to the luteal phase, suggesting that women’s genital arousal may be sensitive to fertility status with respect to sexual activity (specifically, couple sex), but not gender. Subjective arousal was not influenced by fertility status. This study is the first to provide evidence that women’s genital arousal may be influenced by the probability of conception. / Thesis (Master, Psychology) -- Queen's University, 2011-09-29 08:51:26.973