Age at first sexual intercourse, genes, and social context: Evidence from twins and the dopamine D4 receptor gene

We carried out two distinct types of genetic analysis with data from the National Longitudinal Study of Adolescent Health. The first was a non-DNA twin analysis using monozygotic (identical) and same-sex dizygotic (fraternal) twins. The second analysis investigates the association between age at first sexual intercourse and the 48-bp repeat polymorphism in the dopamine receptor D4 gene (DRD4). The twin analysis shows that MZ twins correlate their timing of first sex to a much greater extent than do the same-sex DZ twins. Our analysis of the polymorphisms in DRD4 indicates that those with an any-3R genotype experienced a risk of first sexual intercourse 23% (p = .016), 233% (p = .0001), 28% (p = .012), and 69% (p = .006) higher than those with an other/other (or any-4R) genotype in the all-ethnicities (n = 2,552), Asian, white, and Hispanic samples, respectively. The risk of first sex does not differ between the two genotypes in the African American sample. These results were obtained after adjusting the standard socioeconomic covariates, including gender, parental education, family structure, and community poverty in the regression model. Evidence from both twin and genetic-variant analyses points to a role of genes in the timing of first sexual intercourse.     

Intimate Partner Violence,Minority Stress,and Sexual Risk-Taking Among U.S. Men Who Have Sex With Men

This article examines the prevalence of intimate partner violence (IPV) among a national sample of Internet-recruited U.S. men who have sex with men (MSM) (n = 1,575), and associations between reporting of IPV, minority stress, and sexual risk-taking. Five outcomes are examined: experiences of physical and sexual violence, perpetration of physical and sexual violence, and unprotected anal intercourse (UAI) at last sexual encounter. MSM who reported experiencing more homophobic discrimination and internalized homophobia were more likely to report experiences of IPV. The results point to the need for prevention messages to address the external and internal stressors that influence both violence and sexual risk among MSM.     

HIV Risk Among Men Who Have Sex with Men Only (MSMO) and Men Who Have Sex with Men and Women (MSMW) in Baltimore

Men who have sex with men and women (MSMW) are at high risk for HIV. However, the majority of research on populations of men who have sex with men (MSM) combines MSMW and men who have sex with men only (MSMO) samples, which limits our understanding of HIV risk behaviors and factors associated with HIV risk among MSMW populations. We used the BESURE-MSM2, a venue-based cross-sectional study of HIV risk behaviors among MSM in Baltimore, MD, to examine HIV risk among MSMW. MSMW were less likely to report unprotected receptive anal intercourse than MSMO (6.8% vs. 19.6%, p = .0024). Among MSMW, 43.0% reported unprotected sex with a woman in the past year, but only 19.4% reported unprotected sex with both men and women, representing only 5.0% of the total MSM sample. In multivariate analyses, we found that among MSMW having unprotected sex with women in the past year, disclosing same sex behavior and having a main female partner were associated with unprotected anal intercourse with male partners. HIV prevention programs for MSMW are needed that address the complex partnerships of MSMW and the social contextual factors within which relationships and behaviors are embedded.     

Latino Gay and Bisexual Men's Relationships with Non-Gay-Identified Men Who Have Sex With Men

This study investigated relationships between Latino gay-identified men in metropolitan New York City and their non-gay-identified male partners. Phase 1 consisted of in-depth interviews (N = 33), and Phase 2 consisted of quantitative surveys (N = 120) with Brazilian, Colombian, and Dominican men who have sex with men (MSM). A majority of participants reported having had sex with heterosexually identified men, and in many cases, the relationship was sustained over time. We found mixed results concerning an attitude sometimes attributed to Latinos that sexual orientation is defined by sexual role, with receptive MSM seen as gay and insertive MSM seen as straight. Although there were no significant associations between partner sexual orientation and unprotected anal intercourse, gay men were less likely to take the insertive role in oral or anal sex with straight-identified male partners than with gay partners.     

Psychosocial maturity and teenage contraceptive use: An investigation of decision-making and communication skills

The developmental factors influencing teenage women's contraceptive decision-making with first sexual partner are investigated. A discriminant function analysis of results of a study of 17- to 19-year-old women shows the following: Pill users are distinguished from women who have not used any method by having had a longer relationship with their partner, having a more negative attitude towards becoming premaritally pregnant themselves, being older at the time of their sexual debut, engaging in more frequent sexual intercourse, being more trusting of their partner, and perceiving the risks of unprotected pregnancy as greater. Women who are protected by the use of condom are distinguished from women not protected by any method by having had more discussions with male friends about a variety of topics, having better role-taking skills, having a less negative attitude about becoming premaritally pregnant, and having discussed their sexual debut with their partner beforehand. Results are consistent with a conceptualization which distinguishes contraceptive methods on the basis of the psychosocial costs their use incurs for young women.Research supported by Grant #HD09813, National Institute of Child Health & Human Development. Thanks are due to Robin Halliday, Allyson Myhre, and Carolyn Scheve for help in conducing this investigation.     

Consideration of future consequences and unprotected anal intercourse among men who have sex with men

This study of men who have sex with men (MSM) examined whether tendencies to consider the future consequences of one's actions were associated with sexual behaviors that place oneself at risk for HIV infection. A total of 339 HIV-negative MSM responded to the Consideration of Future Consequences Scale (CFC; Strathman et al., 1994) and to questions about their anal intercourse practices in the past year. In bivariate analyses, men with a stronger future orientation were less likely to engage in anal intercourse unprotected by a condom (p < .05). Multivariate analyses revealed that CFC accounted for significant variance in three of four measures of unprotected anal sex after statistically controlling for demographic covariates (education, income, ethnicity, age). CFC was a better predictor of sexual behavior and accounted for more unique variance than any of the demographic factors. Additional research is needed to confirm that CFC is an antecedent of behavior and to examine the feasibility and efficacy of focusing on CFC in HIV prevention interventions.     

Sexual violence at first intercourse against women in Moshi, northern Tanzania: prevalence, risk factors, and consequences

To explore the relationship between sexual violence at first intercourse and later sexually transmitted infections (STIs) in Moshi, Tanzania, we analysed data from a representative household survey that comprised face-to-face interviews with 1,835 women and tests for six STIs on biological samples from 1,235 of these women. Overall, 10.9 per cent report forced first intercourse and 15.3 per cent report unwanted first intercourse. Unadjusted analysis shows a relationship between forced first intercourse and STIs (OR: 1.72, 95 per cent CI: 1.19-2.51). Life-course variables mediate this relationship. Significant predictors of having an STI include older age, more sexual partners, and a partner who has children with other women. Coerced first intercourse appears to be associated with changes in the life course of women and with a heightened risk of contracting an STI.     

Premarital first births: The influence of the timing of sexual onset versus post-onset risks in the United States

Motivated by long-standing debates between abstinence proponents and sceptics, we examine how socio-economic factors influence premarital first births via: (i) age at first sexual intercourse and (ii) the risk of a premarital first birth following the onset of sexual activity. Factors associated with an earlier age at first intercourse will imply more premarital first births owing to increased exposure to risk, but many of these same factors will also be associated with higher risks of a premarital first birth following onset. Our analyses confirm previous findings that women from disadvantaged backgrounds are younger at first intercourse and have higher premarital first-birth risks than women from more advantaged backgrounds. However, differences in onset timing have a strikingly smaller influence on premarital first-birth probabilities than do differences in post-onset risks. Our findings thus suggest that premarital first births result primarily from differences in post-onset risk behaviours as opposed to differences in onset timing.     

The seasonality of conception

Individual data on menstrual cycles of noncontracepting women living in Western countries were used in order to verify whether the biological seasonality of conception persists after sexual behavior is controlled for. Episodes of intercourse were recorded daily, and the time of ovulation was detected by a marker We find that the seasonality of conception changes with woman's age and frequency of episodes of sexual intercourse. In particular; for women aged 27-31 having only one act of intercourse during the six most fertile days of the menstrual cycle, the seasonality of fecundability is stronger In this age group in the Northern Hemisphere, if seasonality of acts of sexual intercourse is controlled, the monthly distribution of probability of conception is bimodal, with two maxima (September and January) and two minima (December and March). When unobserved characteristics of the couples are considered, this seasonal pattern of conception persists.     

Differences in Risky Sexual Behavior According to Sexual Orientation in Korean Adolescents

Adolescents in sexual minority groups are known to be at risk of contracting sexually transmitted diseases through risky sexual behavior. However, few studies have examined associations between sexual orientation and risky sexual behavior and sexually transmitted diseases in Korean adolescents. Therefore, this cross-sectional study used raw data from the Tenth Korea Youth Risk Behavior Web-Based Survey to explore these relationships. Logistic regression analyses were performed to examine the associations between risky sexual behavior and sexual orientation in adolescents. The participants were 6,884 adolescents who provided data regarding demographic characteristics, sexual orientation, and risky sexual behavior. The proportions of homosexual and bisexual subjects who used condoms, engaged in sexual intercourse after drinking alcohol, and experienced sexually transmitted diseases were higher relative to those of heterosexual subjects. Associations between homosexuality and bisexuality and sexually transmitted diseases and engagement in sexual intercourse after drinking remained after multivariate adjustment. Interventions to prevent risky sexual behavior should target sexual orientation, to improve sexual health and prevent sexually transmitted disease in homosexual and bisexual adolescents.     

India’s ‘Missing Women’ and Men’s Sexual Risk Behavior

Although scholars and policymakers have long been concerned with the ??missing women?? of India, little rigorous research has examined the consequences of India??s sex ratio imbalance for young men??s sexual risk behavior and reproductive health. We use data from the third wave of India??s 2005?C2006 National Family and Health Survey to examine the influence of the community female-to-male sex ratio at ages 10?C39 on men??s likelihood of marrying early in life, of engaging in premarital, multi-partnered, and commercial sex, and of contracting a sexually-transmitted disease. We estimate logistic regression models that control for respondents?? demographic and socioeconomic status and that adjust for the clustering of observations within communities. Net of the effects of other characteristics, the female-to-male sex ratio is positively and significantly associated with the likelihood that men marry prior to age 18 and inversely and significantly associated with the odds that men have had intercourse with a commercial sex worker. However, no significant net associations are observed between the sex ratio and the other outcomes. Education, wealth, religious affiliation, caste, and geographic region emerge as significant predictors of Indian men??s sexual risk behaviors.     

Exploring First Sexual Intercourse,Sexual Orientation,and Sexual Health in Men

In this study the characteristics of the sexual debut of men who have sex with men (MSM) and men who have sex with women (MSW) age 35 or younger (N = 1,201) were compared with one another. We investigated whether these characteristics were associated with sexual health and behavior, and to what extent. Compared to MSW, MSM tended to be older when they had their first sexual intercourse; their first sex partner was older, they felt less ready, and they experienced more pain. We also found that they reported a higher number of lifetime sexual partners and less condom use compared to MSW. Similarities were also ascertained, such as the fact that individuals from both groups do not differ significantly regarding how they experienced their first sexual intercourse emotionally. Many differences between these groups should not always be seen as problematic, whereas others still indicate a need for targeted interventions.     

Mirror Rubbing: A Critical Genealogy of Pre-Modern Chinese Female Same-Sex Eroticism

This article offers a critical genealogy of pre-modern Chinese female same-sex relationships. Through the analysis of the primary source materials in history, fiction, and drama, the author shows that female homosexuality is silenced and suppressed. To Confucianism, female same-sex relationships threaten to exclude men from accessing female sex and keep women away from participating in extending the family line. Even the Daoist theory of sex can be used to discriminate against female homosexuality by denying women the ability to initiate and maintain the cycle of yin-yang interaction in sexual intercourse. There are 2 recurring themes in the male writers' imaginings of female same-sex eroticism. First, heterosexuality is the preferred sexual order, and female same-sex desire arises due to the lack of sexual access to men. Second, heterosexual relationships and intercourse are the norm that female homosexuality aspires to imitate.     

Facing Age: Women Growing Older in an Anti-Aging Culture,by Laura H. Clarke

This is a pilot study exploring intimacy and self esteem in older black women. Twenty six married, urban, non-institutionalized African American women over the age of 60 were interviewed in this investigation. Information concerning their intimate relationships with their spouses and its relationship to their self esteem was gathered. Subjective passages are examhed to accent these relationships. These women were, generally, open about the quality of the relationship between themselves and their spouses. They reported relatively high levels of intimate relations. In particular they described the sub-factors of intimacy such as affection, friendship and a sense of empathy to be positively associated with self esteem. Interestingly, higher frequency of sexual intercourse was seen to be negatively associated with self esteem for these older women. Implications of these findings are discussed.     

Non-Heterosexuality,Relationships, and Young Women’s Contraceptive Behavior

Non-heterosexual young women have a higher rate of unintended pregnancy than their heterosexual peers, but their fertility behaviors are understudied. We use longitudinal data from the Relationship Dynamics and Social Life study to investigate mechanisms contributing to non-heterosexual women’s higher pregnancy risk. These data include weekly reports of relationships, sex, and contraceptive use over 30 months. We compare the relationships and fertility behaviors of three groups: exclusively heterosexual (consistent heterosexual behavior, identity, and attraction); mostly heterosexual (heterosexual identity with same-sex behavior and/or same-sex attraction); and LGBTQ (any non-heterosexual identity). We find that mostly heterosexual and LGBTQ women behave differently from exclusively heterosexual women in ways likely to elevate their risk of unintended pregnancy: more distinct partners during the study period, more sexual intercourse with men, less frequent contraceptive use, less use of a dual method (condom plus hormonal method), and more gaps in contraceptive coverage. Mostly heterosexual women resemble LGBTQ women in their contraceptive behavior but have significantly more intercourse with men, which may increase their pregnancy risk relative to both LGBTQ and exclusively heterosexual women. We conclude by considering implications for LGBTQ health and the measurement of sexual minority populations.     

Contraceptive Method Choice Among Youth in the United States: The Importance of Relationship Context

We examine the relationship characteristics associated with contraceptive method choice within young people’s nonmarital sexual relationships, using data from retrospective relationship histories available in the third wave (2001–2002) of the National Longitudinal Study of Adolescent Health. Data-reduction techniques produce a detailed multidimensional characterization of relationship commitment for nonmarital sexual relationships. We then use multilevel analysis to estimate associations between two key relationship characteristics—relationship commitment and couple heterogamy—and the type of contraceptive method used at last sexual intercourse within each relationship. Results indicate that for a given individual, contraceptive method choice varies across relationships as a function of these characteristics, even after we account for important individual and family characteristics and prior relationship experiences.     

Risk-taking and contraceptive behavior among unmarried college students

The contraceptive behavior of sexually active, never-married college women was examined using multiple regression analyses. Use of an effective method of contraception was highly situation-specific: length of relationship and frequency of intercourse were the variables most highly correlated with use of effective contraception, followed by method of contraception used at first coitus and knowledge of reproduction. Failure to use effective contraception was not associated with low estimates of pregnancy risk, nor with high utility of pregnancy, nor with uniquely high willingness to seek abortion. The results of the present study suggest that use or non-use of effective contraception is mediated by the predictability of sexual intercourse.We would like to thank Ira H. Bernstein for his assistance with computer programming and data analysis. Reprints are available from Ms. Irene Steeger, Center for Population and Family Health, Columbia Unviersity, New York.     

Incorporating heterogeneous intercourse records into time to pregnancy models

Information on the timing of intercourse relative to ovulation can be incorporated into time to pregnancy models to improve the power to detect covariate effects, to estimate the day-specific conception probabilities, and to distinguish between biological and behavioral effects on fecundability, and therefore the probability of conception in a menstrual cycle. In this paper, Bayesian methods are proposed for joint modeling of intercourse behavior and biologic fecundability. The model accommodates a sterile subpopulation of couples, general covariate effects, and heterogeneity among fecund couples in menstrual cycle viability and in frequency of unprotected intercourse. Methods are described for incorporating cycles with varying amounts of intercourse information into a single analysis. A Markov chain Monte Carlo algorithm is outlined for estimation of the posterior distributions of the unknowns. Themethods are applied to data from a North Carolina study of couples attempting pregnancy.     

Sexual activity and weekly contraceptive use among young adult women in Michigan

Past studies on the influence of sexual activity on contraceptive behaviours are inconclusive, relying heavily on cross-sectional data. We used a population-based longitudinal sample of young women in Michigan to evaluate weekly associations between sexual activity and contraceptive use at three levels of measurement: comparing between women, among individual women’s partnerships, and from week to week within partnerships. We used multinomial logistic regression accounting for correlations within partnerships and women. Relative to use of least effective methods, weekly sexual activity was significantly associated with increased use of condoms, pills, and highly effective methods. For pills and highly effective methods, partnership-, woman-, and week-level effects were similar. For condoms, there was no significant woman-level effect. Evidence of immediate effects of sexual activity on contraceptive use highlights the importance of longitudinal data. These dynamics may be diluted or missed altogether when relying on cross-sectional data approaches that compare groups of individuals.