Modeling US blood donor deferrals under a policy of individual risk assessment for HIV risk sexual behavior.

BACKGROUND: In May 2023, the Food and Drug Administration (FDA) released final guidance for blood donor eligibility that recommended the elimination of 3-month deferral for men who have sex with men (MSM) and the related deferral for women who have sex with MSM. In its place, FDA introduced an individual risk assessment policy of asking all presenting blood donors, regardless of sex or gender, if they have had a new partner or more than one sexual partner in the last 3 months and deferring those who also report anal sex (penile-anal intercourse) during this period. We modeled the possible impact of this policy on the US blood donor base. STUDY DESIGN AND METHODS: We developed a computational model to estimate the percentage of blood donors who would be deferred under a policy of individual HIV risk assessment. The model incorporated demographic information about donors and national survey data on HIV risk behaviors and included age and sex distributions and dependencies. RESULTS: Our model estimates that approximately 1.2% of US blood donors would be deferred under the individual HIV risk assessment paradigm. DISCUSSION: The model predicts a relatively minor effect of replacing the time-based deferral for MSM with individual risk-based deferral for sexual behavior. As US blood centers implement this new policy, the effect may be mitigated by donor gains, which warrant further study. The new policy is unlikely to adversely affect the availability of blood and blood components.

Structural brain morphology in young adult women who have been choked/strangled during sex: A whole-brain surface morphometry study.

INTRODUCTION: Being choked/strangled during partnered sex is an emerging sexual behavior, particularly prevalent among young adult women. Using a multiparameter morphometric imaging approach, we aimed to characterize neuroanatomical differences between young adult women (18-30 years old) who were exposed to frequent sexual choking and their choking naïve controls. METHODS: This cross-sectional study consisted of two groups (choking [≥4 times in the past 30 days] vs. choking-naïve group). Participants who reported being choked four or more times during sex in the past 30 days were enrolled in the choking group, whereas those without were assigned to the choking naïve group. High-resolution anatomical magnetic resonance imaging (MRI) data were analyzed using both volumetric features (cortical thickness) and geometric features (fractal dimensionality, gyrification, sulcal depth). RESULTS: Forty-one participants (choking n = 20; choking-naïve n = 21) contributed to the final analysis. The choking group showed significantly increased cortical thickness across multiple regions (e.g., fusiform, lateral occipital, lingual gyri) compared to the choking-naïve group. Widespread reductions of the gyrification were observed in the choking group as opposed to the choking-naïve group. However, there was no group difference in sulcal depth. The fractal dimensionality showed bi-directional results, where the choking group exhibited increased dimensionality in areas including the postcentral gyrus, insula, and fusiform, whereas decreased dimensionality was observed in the bilateral superior frontal gyrus and pericalcarine cortex. CONCLUSION: These data in cortical morphology suggest that sexual choking events may be associated with neuroanatomical alteration. A longitudinal study with multimodal assessment is needed to better understand the temporal ordering of sexual choking and neurological outcomes.

Prevalence and characteristics of choking/strangulation during sex: Findings from a probability survey of undergraduate students.

OBJECTIVE: In a random sample of undergraduate students, we aimed to: (1) establish the prevalence of choking and being choked; (2) examine demographic and situational predictors of being choked, and (3) examine demographic and situational predictors of choking someone.Participants: 4168 randomly sampled undergraduates at a large public U.S. university.Methods: A cross-sectional, confidential online survey.Results: We found that 26.5% of women, 6.6% of men, and 22.3% of transgender and gender non-binary participants reported having been choked during their most recent sexual event. Additionally, 5.7% of women, 24.8% of men, and 25.9% of transgender and non-binary participants reported that they choked their partner at their most recent event. Choking was more prevalent among sexual minority students.Conclusions: Choking is prevalent among undergraduate students; implications for college sexual health education are discussed.

Masturbation Prevalence, Frequency, Reasons, and Associations with Partnered Sex in the Midst of the COVID-19 Pandemic: Findings from a U.S. Nationally Representative Survey.

Despite well-documented individual, relational, and health benefits, masturbation has been stigmatized and is understudied compared to partnered sex. In a US nationally representative survey of adults, we aimed to: (1) assess the prevalence and frequency of participants' prior-year masturbation, (2) describe reasons people give for not masturbating, (3) describe reasons people give for masturbating, and (4) examine the association between masturbation frequency and actual/desired partnered sex frequency in the prior year. Significantly more men than women reported lifetime masturbation, past month masturbation, and greater masturbation frequency. The most frequently endorsed reasons for masturbating related to pleasure, feeling "horny," stress relief, and relaxation. The most frequently endorsed reasons for not masturbating were lack of interest, being in a committed relationship, conflict with morals or values, or being against one's religion. Among women, those who desired partnered sex much more often and a little more often were 3.89 times (95% CI: 2.98, 5.08) and 2.07 times (95% CI: 1.63, 2.62), respectively, more likely to report higher frequencies of past-year masturbation than those who desired no change in their partnered sex frequency. Among men, those who desired partnered sex much more often and a little more often were 4.40 times (95% CI: 3.41, 5.68) and 2.37 times (95% CI: 1.84, 3.06), respectively, more likely to report higher frequencies of past-year masturbation activity than those who reported that they desired no change in their current partnered sex frequency. Findings provide contemporary U.S. population-level data on patterns of adult masturbation.

Association of Frequent Sexual Choking/Strangulation With Neurophysiological Responses: A Pilot Resting-State fMRI Study.

Being choked or strangled during partnered sex is an emerging sexual behavior, prevalent among young adult women. The goal of this study was to test whether, and to what extent, frequently being choked or strangled during sex is associated with cortical surface functioning and functional connectivity. This case-control study consisted of two groups (choking vs. choking-naïve). Women who were choked 4 or more times during sex in the past 30 days were enrolled into the choking group, whereas those without were assigned to the choking-naïve group. We collected structural and resting-state functional magnetic resonance imaging (fMRI) data and analyzed the data for amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) using cortical surface-based resting-state fMRI analysis, followed by static and dynamic resting-state fMRI connectivity analysis. Forty-one participants (choking n = 20; choking-n-aïve n = 21) contributed to the analysis. An inter-hemispheric imbalance in neuronal activation pattern was observed in the choking group. Specifically, we observed significantly lower ALFF and ReHo in the left cortical regions (e.g., angular gyrus, orbitofrontal gyrus) and higher ALFF and ReHo in the right cortical regions (e.g., pre-central/post-central gyri) in the choking group compared with the choking-naïve group. A significant group difference was found in static functional connectivity between the bilateral angular gyrus and the whole brain, in which the choking group's angular gyrus showed hyperconnectivity with, for example, the post-central gyrus, pre-central gyrus, and Rolandic operculum, relative to the choking-naïve group. The dynamic analysis revealed hyperconnectivity between the left angular gyrus and the bilateral postcentral gyrus in the choking group compared with the choking-naïve group. Taken together, our data show that multiple experiences of sexual choking/strangulation are associated with an inter-hemispheric imbalance in neural activation pattern and hyperconnectivity between the angular gyrus and brain regions related to motor control, consciousness, and emotion. A longitudinal study using multi-modal neurological assessments is needed to clarify the acute and chronic consequences of sexual choking/strangulation.

The Impact of Household Context on Self-Perceived Changes in Solo and Partnered Sexual Behaviors During the COVID-19 Pandemic: Findings from a U.S. Probability Survey.

To understand how household context factors impacted self-reported changes in solo and sexual behaviors in U.S. adults during early stages of the COVID- 19 pandemic, we conducted an online, nationally representative, cross-sectional survey of U.S. adults (N = 1010; aged 18-94 years; 62% response rate) from April 10-20, 2020. We used weighted descriptive statistics with Wilcoxon rank sign tests to understand the population prevalence and significance of self-reported changes (five-point scale: much less to much more) in 10 solo and partnered sexual behaviors. Ordinal regression was used to assess the impact of household predictor variables-including number of children at home, number of adults in home, partnership status (unpartnered, partnered and not living together, partnered and living together) and employment status (not working, employed not as essential worker, employed as essential worker). All models were adjusted for gender, age, sexual orientation, race/ethnicity, and residence location (urban, suburban, rural).All solo and partnered sexual behaviors showed some amount of significant change-increased activity for some and decreased for others-for U.S. adults during the pandemic. Not living with a partner was broadly associated with decreased affectionate partnered sexual behaviors; unpartnered adults reported increased sexting. Individuals not employed reported increased oral sex and increased consumption of sexually explicit materials as compared to non-essential workers. Number of children at home and household size were not significantly linked to self-reported behavior change. Ongoing sexual health-focused research should continue to focus on understanding how adults manage opportunities and constraints to their sexual lives in the context of a still-going pandemic. While many aspects of social life look more "normal" (e.g., many people have returned to their in-person offices and children are largely back in school), new and more-infectious strains of COVID-19 have proven that the pandemic may still yet impact daily living. Lessons learned from COVID need to include sexual health planning both for any future strains of COVID, as well as for future public health emergencies.

Sexual Repertoire, Duration of Partnered Sex, Sexual Pleasure, and Orgasm: Findings from a US Nationally Representative Survey of Adults.

In a confidential U.S. nationally representative survey of 2,525 adults (1300 women, 1225 men), we examined participants' event-level sexual behaviors, predictors of pleasure and orgasm, and perceived actual and ideal duration of sex, by gender and age. Event-level kissing, cuddling, vaginal intercourse, and oral sex were prevalent. Sexual choking was more prevalent among adults under 40. While women and men reported a similar actual duration of sex, men reported a longer ideal duration. Participants with same-sex partners reported a longer ideal duration than those with other-sex partners. Finally, findings show that gendered sexual inequities related to pleasure and orgasm persist.

Frequency, Method, Intensity, and Health Sequelae of Sexual Choking Among U.S. Undergraduate and Graduate Students.

Although sexual choking is now prevalent, little is known about how people engage in choking in terms of frequency, intensity, method, or potential health sequelae. In a campus-representative survey of undergraduate and graduate students, we aimed to: (1) describe the prevalence of ever having choked/been choked as part of sex; (2) examine the characteristics of choking one's sexual partners (e.g., age at first experience, number of partners, frequency, intensity, method); (3) examine the characteristics of having been choked during sex; and (4) assess immediate responses of having been choked including the extent to which frequency and method (e.g., hand, ligature, limb) of having been choked predicts the range of responses endorsed by participants. A total of 4254 randomly sampled students (2668 undergraduate, 1576 graduate) completed a confidential online survey during Spring 2021. The mean age of first choking/being choked was about 19, with more undergraduates than graduate students reporting first choking/being choked in adolescence. Women and transgender/gender non-binary participants were significantly more likely to have been choked than men. Participants more often reported the use of hands compared to limbs or ligature. Common responses to being choked were pleasurable sensations/euphoria (81.7%), a head rush (43.8%), feeling like they could not breathe (43.0%), difficulty swallowing (38.9%), unable to speak (37.6%), and watery eyes (37.2%). About 15% had noticed neck bruising and 3% had lost consciousness from being choked. Greater frequency and intensity of being choked was associated with reports of more physical responses as was use of limb (arm, leg) or ligature.

Frequent and Recent Non-fatal Strangulation/Choking During Sex and Its Association With fMRI Activation During Working Memory Tasks.

Being strangled, or "choked," by a sexual partner has emerged as a prevalent, often wanted and consensual sexual behavior among adolescent and young adult women, yet the neurological consequences of repeated exposure to this behavior are unknown. The objective of the study was to examine the association between a history of repeated, recent choking/strangling episodes during sex and fMRI activation during working memory tasks in young adult women. This case-control study involved young adult women (18-30 years old) at a large, public university, and consisted of two study groups: a choking group consisting of participants who were recently and frequently choked/strangled during sex by a partner (≥4 times in the past 30 days) and a choking-naïve (control) group who had never been choked/strangled during sex. Participants completed two variations of the N-back (0-back, 1-back, and 2-back) working memory task during functional magnetic resonance imaging (fMRI): verbal and visual N-back tasks. Data from 20 participants per group were available for analysis. Between-group differences for accuracy and reaction time were not significant for either variation of the N-back task. Significant differences in fMRI activation patterns were detected between the choking and the choking-naïve groups for the three contrasts of interest (1-back > 0-back, 2-back > 0-back, and 2-back > 1-back). The choking group exhibited increased activation in multiple clusters relative to the choking-naïve group for the contrasts between the 1-back and 2-back conditions compared to the 0-back conditions (e.g., superior frontal gyrus, corpus callosum). However, the choking-naïve group exhibited increased activation relative to the choking group in several clusters for the 2-back > 1 back contrast (e.g., splenium, middle frontal gyrus). These data indicate that recent, frequent exposure to partnered sexual strangulation is associated with different neural activation patterns during verbal and visual working memory tasks compared to controls, suggesting that being choked/strangled during sex may modify the allocation of neural resources at increasing levels of cognitive load. Further investigation into the neurologic effects of this sexual behavior is warranted, given the prevalence of sexual choking among adolescent and young adult women.

Asexual or not sure: Findings from a probability sample of undergraduate students.

OBJECTIVE: Present study aims to: 1) examine demographic correlates of LGB, asexual, or not sure participants 2) describe the prevalence of diverse sexual behaviors, 3) assess the prevalence of event-level sexual behaviors and 4) examine predictors of sexual pleasure. PARTICIPANTS: 761 non-heterosexual undergraduates at a large, public U.S. university. METHODS: Randomly sampled undergraduate students completed a confidential, cross-sectional online survey. RESULTS: Of 761 non-heterosexual respondents; 567 identified as LGB, 47 asexual, and 147 not sure. Asexual students, those not sure were less likely to report having engaged in solo and partnered sexual activities and report sexual activities being less pleasurable at most recent sexual event, compared with LGB students. This difference (relative to LGB) became nonsignificant when accounting for reported sexual activities. CONCLUSIONS: Our findings inform how college students define and experience their sexual identities and assist college health professionals in training on sexuality and prevention of risk factors.

Porn Sex versus Real Sex: Sexual Behaviors Reported by a U.S. Probability Survey Compared to Depictions of Sex in Mainstream Internet-Based Male-Female Pornography.

Using data from a 2014 U.S. nationally representative probability survey and a 2014 content analysis of 2562 male-female videos from two popular pornographic websites, this study aimed to: (1) compare the prevalence of survey respondents' event-level sexual behaviors with those depicted in mainstream pornography online videos; (2) compare event-level condom use with condom use prevalence in pornographic videos; (3) compare event-level orgasm with prevalence of orgasms in pornographic videos; and (4) assess whether respondents' partnered use of pornography was associated with the sexual behaviors in which they report engaging. We found that kissing, male orgasm, female orgasm, and condom use were significantly less prevalent in the pornographic videos than in survey respondents' most recent sexual experiences. Conversely, penile-anal intercourse and fellatio were significantly more prevalent in the pornographic videos than in participants' reports of their most recent sexual experience. There were no significant differences between the prevalence of cunnilingus or sex toy use represented in the videos as compared to survey respondents' reports. Finally, we found that individuals who reported partnered pornography use during their most recent sexual experience were more likely to report having engaged in oral sex, penile-anal intercourse, and sex toy use and were also more likely to report female orgasm during their most recent sexual experience.

Meanings of Rough Sex across Gender, Sexual Identity, and Political Ideology: A Conditional Covariance Approach.

The purpose of this study was to investigate how various subgroups based on gender, sexual identity, and political ideology conceptualize rough sex. We used available data from a 2020 survey of randomly sampled undergraduate students at a large public university in the Midwestern U.S. (n = 4,989). The dichotomous responses to 13 items on the rough sex meaning scale were analyzed using a conditional covariance approach to better understand which behaviors commonly described as rough sex behaviors were prevalent. Our results showed that rough sex was conceptualized largely as a two-dimensional construct for vast majority of subgroups. Across all subgroups, nine of the 13 behaviors clustered along two dimensions in the same way. Specifically, four behaviors related to hair pulling, being pinned down, hard thrusting, and throwing someone onto a bed clustered together as one dimension (spanking and tearing clothes off being present along this dimension for vast majority of the subgroups). Being tied up, slapping, choking, punching, and making someone have sex behaviors formed a separate dimension of rough sex across all studied groups (with biting and scratching being associated with this dimension for vast majority of subgroups).

Sex and Relationships Pre- and Early- COVID-19 Pandemic: Findings from a Probability Sample of U.S. Undergraduate Students.

In the wake of the COVID-19 pandemic, most U.S. colleges closed their campuses-including residence halls-causing significant disruption to students' lives. Two waves of data were collected from undergraduate students enrolled at a large U.S. Midwestern university: Wave 1 was a confidential online survey of 4989 randomly sampled undergraduate students collected in January/February 2020; Wave 2 was collected in April/May 2020 following campus closure. Our research aimed to: (1) assess how the COVID-19 related campus closure affected college students' romantic/sexual relationships, (2) examine students' past month sexual behaviors prior to the pandemic in comparison with their sexual behaviors during campus closure, and (3) compare participants' pre-pandemic event-level sexual behaviors with those occurring during campus closure. Of 2137 participants who completed both waves (49.8% women, mean age = 20.9), 2.6% were living at home in Wave 1 compared to 71.0% at Wave 2. Of those in relationships, 14.5% experienced a breakup and 25.3% stayed in their relationship but returned home to different cities. There were no statistically significant differences in participants' prior month reports of solo masturbation or sending/receiving nude/sexy images between Waves 1 and 2; however, participation in oral, vaginal, and anal sex significantly decreased across waves. Examining participants' most recent sexual events, Wave 2 sex more often occurred with a cohabiting or relationship partner and was rated as more wanted, emotionally intimate, and orgasmic. Implications for sexual health professionals are discussed.

Relationships between Penile-Vaginal Intercourse Frequency and Condom/Contraceptive Use from 2009 to 2018: Findings from the National Survey of Sexual Health and Behavior.

Objectives: To examine changes over time in event-level condom/contraceptive use and the association between past year penile-vaginal intercourse frequency and event-level condom/contraceptive use. Methods: Data were from the 2009 and 2018 National Survey of Sexual Health and Behavior, an online probability survey of U.S. adolescents and adults. Results: Use of condoms and highly effective hormonal contraceptives decreased while long-acting reversible contraceptive use increased from 2009 to 2018 among adults. Increased penile-vaginal intercourse frequency was associated with decreased use of most contraceptive methods but an increase in condom use for adolescents. Conclusions: Sexual frequency should be considered when assessing condom/contraceptive use.

Associations between sexual precedent and sexual compliance: An event-level examination.

Objective Most studies on agreeing to unwanted sex have assessed sexual encounters between people who have had sex before. Thus, we examined instances of sexual compliance with a novel sexual partner. Participants: A probability sample of college students at a university in the Midwest United States (N = 7,112). Methods: Participants completed an online survey based on measures from the National Survey of Sexual Health and Behavior. Results: Only 2.5% (n = 179) agreed to unwanted sexual activity at their most recent sexual encounter. People who were sexually compliant with a novel sexual partner frequently did so due to their own alcohol intoxication. Further, sexual compliance with novel sexual partners was less frequently associated with affectionate sexual behaviors or orgasm. Conclusions: Our initial findings regarding the effect of sexual precedent on sexual compliance warrant further research on instances when people agree to sex they don't want with novel partners.

The relationship between college students' campus sexual health resource utilization and self-reported STI testing: Findings from an undergraduate probability survey.

ObjectiveTo examine the prevalence of student utilization of campus sexual health resources and their association with sexually transmitted infection (STI) testing. Participants: Undergraduate students (n = 7020) at a large Midwestern university completed a confidential online survey in 2015. Methods: A probability-based sample of undergraduate students completed a cross-sectional online survey. Results: Commonly accessed sexual health resources were student orientation activities about sexual assault or rape, sexuality/gender classes, gender and sexual orientation panels, class panels on sexual assault, birth control and STI presentations, and having joined a sexuality-related student organization. Campus sexual health resource utilization was significantly associated with greater STI testing since college. Gender, race, class level, enrollment status, sexual orientation, timing of last sexual event, and perceived STI risk were significantly associated with STI testing in college. Conclusions: Campus sexual health resources play an important role in student sexual health promotion.

Non-Fatal Strangulation/Choking During Sex and Its Associations with Mental Health: Findings from an Undergraduate Probability Survey.

Choking/strangulation during sex is prevalent among young adults in the United States. We examined associations between having ever been choked and participants' current mental health symptoms (e.g., feeling depressed, anxious, sad, lonely) in the prior 30 days and in the prior year. Participants were 4352 randomly sampled undergraduates who completed a confidential online survey and reported lifetime partnered sexual activity. 33.6% of women and 6.0% of men reported having been choked more than five times. After adjusting for demographic characteristics, having been choked remained significantly associated with all four mental health outcomes, except for overwhelming anxiety among men.

Changes in Penile-Vaginal Intercourse Frequency and Sexual Repertoire from 2009 to 2018: Findings from the National Survey of Sexual Health and Behavior.

Solo and partnered sexual behaviors are relevant to health, well-being, and relationships. Recent research shows that sexual frequency has declined in the U.S. and in other countries; however, measurement has been imprecise. We used data from 14- to 49-year-old participants in the 2009 and 2018 waves of the National Survey of Sexual Health and Behavior (NSSHB), a confidential U.S. nationally representative survey that is conducted online. We aimed to: (1) assess changes in frequency of past-year penile-vaginal intercourse and (2) examine combinations of past-year sexual behaviors for each of the two waves. We hypothesized that we would observe lower frequency of penile-vaginal intercourse (PVI) from 2009 to 2018 and that we would observe greater engagement in sexual repertoires involving non-coital partnered behaviors (e.g., partnered masturbation, oral sex) in 2018 as compared to 2009. Participants were 4155 individuals from the 2009 NSSHB (Adolescents: 406 females, 414 males; Adults: 1591 women, 1744 men) and 4547 individuals from the 2018 NSSHB (Adolescents: 416 females, 411 males; Adults: 2007 women, 1713 men). Compared to adult participants in the 2009 NSSHB, adults in the 2018 NSSHB were significantly more likely to report no PVI in the prior year (28% in 2018 vs. 24% in 2009). A similar difference in proportions reporting no PVI in the prior year was observed among 14-17-year-old adolescents (89% in 2018 vs. 79% in 2009). Additionally, for both adolescents and adults, we observed decreases in all modes of partnered sex queried and, for adolescents, decreases in solo masturbation.

Pleasure During Adolescents' Most Recent Partnered Sexual Experience: Findings from a U.S. Probability Survey.

Compared to studies on sexually transmitted infections and pregnancy prevention, sexual pleasure has received limited attention in the adolescent sexual development literature. In the present study, we used data from 157 adolescents (66 females; 14 to 17 years old), with a partnered sexual experience in the past 12 months to explore adolescents' sexual pleasure. First, we examined adolescents' perceptions of pleasure during their most recent partnered sexual experience. We then used information about those sexual experiences to identify correlates of sexual pleasure. Adolescents' reports of sexual pleasure were mixed. Although 17.8% reported their sexual experience was extremely pleasurable and 36.5% reported it was quite pleasurable, 26.6% indicated moderate pleasure, 13.1% a little pleasure, and 3.3% reported no pleasure. Sexual pleasure was primarily associated with aspects of sexual experiences that reflected socioemotional intimacy and desire. Specifically, cuddling with partners, emotional intimacy, and wantedness were all associated with greater sexual pleasure. Additionally, adolescents found sex more pleasurable when it occurred with a friend, but less pleasurable when it involved genital rubbing. Most sexual behaviors, having experienced orgasm, and the situational context of sexual experiences were not associated with sexual pleasure. Thus, specific sexual behaviors and orgasm may have less impact on sexual pleasure than feelings of emotional intimacy and desire. The diversity of perceived sexual pleasure and its associations with intimacy and desire suggest that, during adolescence, partnered sexual experiences are not primarily motivated by anticipated physical pleasure.

Exercise-Induced Orgasm and Its Association with Sleep Orgasms and Orgasms During Partnered Sex: Findings From a U.S. Probability Survey.

Prior research has described women's experiences with exercise-induced orgasm (EIO). However, little is known about men's experiences with EIO, the population prevalence of EIO, or the association of EIO with other kinds of orgasm. Using U.S. probability survey data, the objectives of the present research were to: (1) describe the lifetime prevalence of exercise-induced orgasm (EIO) and sleep orgasm; (2) assess respondents' age at first experience of EIO as well as the type of exercise connected with their first EIO; (3) examine associations between lifetime EIO experience and orgasm at respondents' most recent partnered sexual event; and (4) examine associations between lifetime EIO experience and sleep orgasms. Data were from the 2014 National Survey of Sexual Health and Behavior (1012 men and 1083 women, ages 14 years and older). About 9% of respondents reported having ever experienced exercise-induced orgasm. More men than women reported having experienced orgasm during sleep at least once in their lifetime (66.3% men, 41.8% women). The mean age for women's first EIO was significantly older than men (22.8 years women, 16.8 years men). Respondents described a wide range of exercises as associated with their first EIO (i.e., climbing ropes, abdominal exercise, yoga). Lifetime EIO experience was associated with lifetime sleep orgasms but not with event-level orgasm during partnered sex. Implications related to understanding orgasm and recommendations for clinicians and sex educators are discussed.