Journal of Sex & Marital Therapy, 33:31���39, 2007 Copyright �� Taylor & Francis Group, LLC ISSN: 0092-623X print DOI: 10.1080/00926230600998458 Intercourse Orgasm Consistency, Concordance of Women���s Genital and Subjective Sexual Arousal, and Erotic Stimulus Presentation Sequence STUART BRODY Division of Psychology, School of Social Sciences, University of Paisley, Paisley, United Kingdom Many studies report discordance between women���s genital (vaginal pulse amplitude) and subjective sexual arousal responses to erotica. Consistent with our previous research, I hypothesized that the as- sociation between physiological and subjective domains would be greater for women with greater orgasmic consistency (OC) during penile-vaginal intercourse but not for OC during masturbation or noncoital partnered sexual activities. I confirmed this specific hy- pothesis in a sample of young Dutch women (N = 27, mean age 20, all with current partners), replicating our earlier psychophysiologi- cal findings with postmenopausal women. Also replicated were the findings that intercourse OC (40% of the women had an orgasm from 90���100% of intercourse events, 44% from 9���89% of inter- course events) was not less than for other sexual activity and that OC during intercourse was uncorrelated with OC during mastur- bation. We observed the association of intercourse consistency with genital-subjective concordance when visual erotica was presented in a sequence of increasing intensity (analogous to typical real sex- ual encounters) but not when presented in decreasing, random, or fixed-intensity sequence. I discuss the results in terms of the unique nature of penile-vaginal intercourse and the study���s implications for sex therapy and sex research. I am grateful to Ellen Laan, who provided the data. Portions of this study were presented at the 45th meeting of the Society for Psychophysiological Research, Lisbon, in September 2005. Address correspondence to Stuart Brody, Division of Psychology, School of Social Sciences, University of Paisley, Paisley PA1 2BE, United Kingdom. E-mail: stuartbrody@hotmail.com 31

32 S. Brody In many studies, the correlation between women���s subjective and genital response to visual or fantasized erotic stimuli has been fairly low (e.g., Laan & Everaerd, 1995). However, in a sample of menopausal women, we (Brody, Laan, & van Lunsen, 2003) found that specifically penile-vaginal intercourse orgasm consistency (but not orgasm consistency during either masturbation or partnered sexual activity that did not include penile-vaginal intercourse) was associated with excellent concordance of genital and subjective measures of sexual arousal. There are many differences between penile-vaginal intercourse and other sexual behaviors, including that only penile-vaginal intercourse fre- quency is associated with indices of better cardiovascular function (Brody, 2006 Brody & Preut, 2003 Brody, Veit, & Rau, 2000), less excess body fat (Brody, 2004), and women���s greater awareness of, ability to identify, and ability to express specific emotions (Brody, 2003). Compared with masturba- tion orgasm, intercourse orgasm leads to a dramatically greater post-orgasmic rise in prolactin levels, suggesting greater physiological satiety, possibly pro- viding one basis (better regulation of central nervous system dopaminergic activity) for intercourse but not other sexual behaviors being associated with indices of better psychological and physiological function (Brody & Kruger,�� 2006). In keeping with our previously confirmed specific hypothesis (Brody et al., 2003), I again hypothesized that consistency of orgasm during penile- vaginal intercourse, but not consistency of orgasm during other sexual behav- iors (whether alone or with a partner), would be associated with a significant correlation between subjective arousal and genital arousal (as measured by vaginal pulse amplitude VPA). I also hypothesized that the association between intercourse orgasm consistency and subjective-genital concordance would be significant for the laboratory condition that presents erotica in a sequence of increasing content intensity (allowing for optimal awareness of increasing genital and subjective arousal over time, providing greater variance in arousal levels, and being more similar to a typical real sexual encounter) but not when the stimuli are presented in decreasing, random, or fixed intensity sequences. Last, I examined the prevalence of intercourse orgasm consistency and both compared it to, and examined the correlations with, orgasm consistency during masturbation or noncoital partnered sexual behavior. METHOD Subjects The subjects were undergraduate psychology students who received course credit for participation. Only women (N = 27) reporting a current partner and no history of being sexually abused were included in the analysis. They first