Jennifer A. Bossio

A Review of the Current State of the Male Circumcision Literature

INTRODUCTION Male circumcision is one of the most commonly performed surgical procedures worldwide and a subject that has been the center of considerable debate. Recently, the American Association of Pediatrics released a statement affirming that the medical benefits of neonatal circumcision outweigh the risks. At present, however, the majority of the literature on circumcision is based on research that is not necessarily applicable to North American populations, as it fails to take into account factors likely to influence the interpretability and applicability of the results. AIMS The purpose of this review is to draw attention to the gaps within the circumcision literature that need to be addressed before significant changes to public policy regarding neonatal circumcision are made within North America. METHODS A literature review of peer-reviewed journal articles was performed. MAIN OUTCOME MEASURES The main outcome measure was the state of circumcision research, especially with regard to new developments in the field, as it applies to North American populations. RESULTS This review highlights considerable gaps within the current literature on circumcision. The emphasis is on factors that should be addressed in order to influence research in becoming more applicable to North American populations. Such gaps include a need for rigorous, empirically based methodologies to address questions about circumcision and sexual functioning, penile sensitivity, the effect of circumcision on mens sexual partners, and reasons for circumcision. Additional factors that should be addressed in future research include the effects of age at circumcision (with an emphasis on neonatal circumcision) and the need for objective research outcomes. CONCLUSION Further research is needed to inform policy makers, health-care professionals, and stakeholders (parents and individuals invested in this debate) with regard to the decision to perform routine circumcision on male neonates in North America.

Does Menstrual Cycle Phase Influence the Gender Specificity of Heterosexual Women’s Genital and Subjective Sexual Arousal?

Unlike men, heterosexual women’s genital arousal is gender nonspecific, such that heterosexual women show relatively similar genital arousal to sexual stimuli depicting men and women but typically report greater subjective arousal to male stimuli. Based on the ovulatory-shift hypothesis—that women show a mid-cycle shift in preferences towards more masculine features during peak fertility—we predicted that heterosexual women’s genital and subjective arousal would be gender specific (more arousal towards male stimuli) during peak fertility. Twenty-two naturally-cycling heterosexual women were assessed during the follicular and luteal phases of their menstrual cycle to examine the role of menstrual cycle phase in gender specificity of genital and subjective sexual arousal. Menstrual cycle phase was confirmed with salivary hormone assays; phase at the time of first testing was counterbalanced. Women’s genital and subjective sexual arousal patterns were gender nonspecific, irrespective of cycle phase. Cycle phase at first testing session did not influence genital or subjective arousal in the second testing session. Similar to previous research, women’s genital and subjective sexual arousal varied with cues of sexual activity, but neither genital nor subjective sexual arousal varied by gender cues, with the exception of masturbation stimuli, where women showed higher genital arousal to the stimuli depicting male compared to female actors. These data suggest that menstrual cycle phase does not influence the gender specificity of heterosexual women’s genital and subjective sexual arousal.

Examining Penile Sensitivity in Neonatally Circumcised and Intact Men Using Quantitative Sensory Testing

PURPOSE Little is known about the long-term implications of neonatal circumcision on the penile sensitivity of adult men, despite recent public policy endorsing the procedure in the United States. In the current study we assessed penile sensitivity in adult men by comparing peripheral nerve function of the penis across circumcision status. MATERIALS AND METHODS A total of 62 men (age 18 to 37 years, mean 24.2, SD 5.1) completed study procedures (30 circumcised, 32 intact). Quantitative sensory testing protocols were used to assess touch and pain thresholds (modified von Frey filaments) and warmth detection and heat pain thresholds (a thermal analyzer) at a control site (forearm) and 3 to 4 penile sites (glans penis, midline shaft, proximal to midline shaft and foreskin, if present). RESULTS Penile sensitivity did not differ across circumcision status for any stimulus type or penile site. The foreskin of intact men was more sensitive to tactile stimulation than the other penile sites, but this finding did not extend to any other stimuli (where foreskin sensitivity was comparable to the other sites tested). CONCLUSIONS Findings suggest that minimal long-term implications for penile sensitivity exist as a result of the surgical excision of the foreskin during neonatal circumcision. Additionally, this study challenges past research suggesting that the foreskin is the most sensitive part of the adult penis. Future research should consider the direct link between penile sensitivity and the perception of pleasure/sensation. Results are relevant to policy makers, parents of male children and the general public.

Women's genital sexual arousal to oral versus penetrative heterosexual sex varies with menstrual cycle phase at first exposure

Reproductive-aged women show increased interest in sexual activity during the fertile phase of the menstrual cycle that can motivate sexual behavior and thereby increase the likelihood of conception. We examined whether women demonstrated greater sexual responses (subjective and genital sexual arousal) to penetrative versus oral sexual activities during the fertile versus non-fertile phases of their cycles, and whether womens arousal responses were influenced by the phase during which they were first exposed to these sexual stimuli (e.g., Slob et al., 1991; Wallen and Rupp, 2010). Twenty-two androphilic women completed two identical sexual arousal assessments in which genital responses were measured with a vaginal photoplethysmograph and their feelings of sexual arousal were recorded. Women viewed an array of 90s films varying by couple type (female-female, male-male, female-male) and sexual activity type (oral or penetrative), during the fertile (follicular) and non-fertile (luteal) phases of their menstrual cycle, with the order of cycle phase at the first testing session counter-balanced. Women tested first in the fertile phase showed significantly greater genital arousal to female-male penetrative versus oral sex in both testing sessions, whereas self-reports of sexual arousal were not affected by cycle phase or testing order. These results contribute to a growing body of research suggesting that fertility status at first exposure to sexual stimuli has a significant effect on subsequent sexual responses to sexual stimuli, and that this effect may differ for subjective versus genital sexual arousal.

Observational Stance as a Predictor of Subjective and Genital Sexual Arousal in Men and Women

Observational stance refers to the perspective a person takes while viewing a sexual stimulus, either as a passive observer (observer stance) or an active participant (participant stance). The objective of the current study was to examine the relationship between observational stance and sexual arousal (subjective and genital) across a range of sexual stimuli that do or do not correspond with a participants sexual attraction (preferred or nonpreferred stimuli, respectively). Regression analyses revealed that, for men (n = 44), participant stance significantly predicted subjective and genital arousal. Womens (n = 47) observer and participant stance predicted subjective arousal but not genital arousal. Analysis of variance showed that participant stance was greatest under preferred sexual stimuli conditions for all groups of participants, while observer stance scores revealed a less consistent pattern of response. This was particularly true for opposite-sex-attracted women, whose ratings of observer stance were lowest for preferred stimuli. Observational stance does not appear to account for gender differences in specificity of sexual arousal; for men, however, participant stance uniquely predicted genital response after controlling for sexual attractions. Similarities in the relationships between mens and womens observational stance and sexual responses challenge previous claims of gender differences in how men and women view erotica.

Menstrual cycle phase predicts women's hormonal responses to sexual stimuli

ABSTRACT A robust body of research has demonstrated shifts in womens sexual desire and arousal across the menstrual cycle, with heightened desire and arousal coincident with heightened probability of conception (POC), and it is likely that ovarian hormones modulate these shifts. However, studies in which women are exposed to audiovisual sexual stimuli (AVSS) at high POC (mid‐follicular) and low POC (luteal) phases have failed to detect significant differences in genital or subjective arousal patterns based on menstrual cycle phase. Here, we tested whether hormonal responsivity to AVSS differs as a function of cycle phase at testing, and whether phase during which participants were first exposed to AVSS influences hormonal responsivity in subsequent test sessions. Twenty‐two naturally cycling heterosexual women were exposed to AVSS during the follicular and luteal phases, with phase at first test session counterbalanced across participants. Salivary samples were collected before and after AVSS exposure. Estradiol increased significantly during both follicular and luteal phase sessions, and increases were higher during the follicular phase. Testosterone (T) increased significantly only during the follicular phase session, while progesterone (P) did not change significantly during either cycle phase. Session order and current cycle phase interacted to predict P and T responses, such that P and T increased during the follicular phase in women who were first tested during the luteal phase. These data suggest that menstrual cycle phase influences hormonal responsivity to AVSS, and contribute to a growing body of clinical and empirical literature on the neuroendocrine modulators of womens sexuality. HIGHLIGHTSWe tested whether hormone responses to AVSS are modulated by cycle phase.E2 and T changed in response to AVSS more during follicular than luteal phase.T and P rose in response to AVSS during follicular phase in women 1st tested in luteal phase.

“Corrigendum to: Women's genital sexual arousal to oral versus penetrative heterosexual sex varies with menstrual cycle phase at first exposure” [Horm. Behav. 65 (2014) 319–327]

The authors regret the omission of the following text from their article: The current study was supported by financial assistance to MLC from the Natural Sciences and Engineering Research Council of Canada (386198-10) and Queens University. We would like to thank S. Dawson, D. Krupp, and M. Seto for their helpful feedback on an earlier version of the manuscript, and D. Puts and S. van Anders for their assistance with hormonal measures.