Associations between forced non-consensual first-sex and HIV among sexually active women in the Kingdom of Eswatini.

Studies continue to underscore the profound impact of sexual violence on women's health. Yet, little is known about the impact, via a complex matrix of behavioural and social factors, of first intercourse, namely forced non-consensual on HIV status, particularly among sexually active women (SAW) in low-income countries where HIV prevalence remains high. Using a national sample from Eswatini, we employed multivariate logistic regression modelling to estimate the associations between forced first-sex (FFS), subsequent sexual behaviour and HIV status among 3555 SAW aged from 15 years to 49 years. The results found that women who experienced FFS had a greater number of sexual partners compared to those who had never experienced FFS (aOR = 2.79, p < .01), although there were no significant differences in condom use, early sexual debut and casual sex involvement between these two groups. FFS remained significantly associated with a higher risk of having HIV (aOR = 1.70, p < .05) even after controlling for risky sexual behaviours and various other factors. These findings further reinforce the relationship between FFS and HIV, and suggest that addressing sexual violence is a critical component of HIV prevention among women in low-income countries.

Low prevalence of bacterial vaginosis in Kenyan adolescent girls and rapid incidence after first sex.

BACKGROUND: Bacterial vaginosis is a risk factor for sexually transmitted infections, including HIV. Adult African women have a high prevalence of bacterial vaginosis, but it is not known when first bacterial vaginosis occurs. OBJECTIVE: This study aimed to describe bacterial vaginosis in younger African women, before and after first sex, and to determine the incidence of bacterial vaginosis and significant correlates of bacterial vaginosis incidence and recurrence. STUDY DESIGN: In a prospective observational cohort study enrolling adolescents with limited sexual experience, young women aged 16 to 21 years were recruited in Thika, Kenya. Eligible participants were HIV and herpes simplex virus 2 seronegative and reported 0 or 1 lifetime sexual partner. The Nugent score was determined at quarterly visits from vaginal Gram stains. The trends in bacterial vaginosis were described over time; hazard ratios were calculated using Cox regression, and relative risk of bacterial vaginosis was estimated using generalized estimating equations and Poisson regression. RESULTS: A total of 400 participants with a median age of 18.6 years (interquartile range, 16-21) were enrolled. Of note, 322 participants (80.5%) reported no history of sex, whereas 78 participants (19.5%) reported sex with 1 partner. At enrollment, bacterial vaginosis (Nugent score of ≥7) was uncommon (21/375 [5.6%]). Overall, 144 participants had bacterial vaginosis at least once, for an incidence rate of 16.5 cases per 100 person-years. Before first sex, bacterial vaginosis was present at 2.8% of visits, compared with 13.7% of visits after first sex. An adjusted model of bacterial vaginosis incidence observed that first sex was associated with more than a 2-fold increased bacterial vaginosis risk (adjusted hazard ratio, 2.44; 95% confidence interval, 1.25-4.76; P=.009). Chlamydia diagnosis (adjusted hazard ratio, 1.73; 95% confidence interval, 1.1-2.8; P=.02), and herpes simplex virus 2 seropositivity (adjusted hazard ratio, 2.88; 95% confidence interval, 1.17-7.09; P=.021) were both associated with incident bacterial vaginosis. A multivariate generalized estimating equation model, including all episodes of bacterial vaginosis, demonstrated risk factors, including first sex, sexually transmitted infections, urban residence, recent sex, and no income; the most important risk factor was first sex (adjusted relative risk, 1.92; 95% confidence interval, 1.12-3.31; P=.018). The probability of bacterial vaginosis increased with each subsequent episode; mean Nugent scores increased after each bacterial vaginosis episode. CONCLUSION: Using detailed longitudinal observation, this study found that Kenyan adolescents have almost no bacterial vaginosis before first sex and that initiation of sexual activity was the strongest risk factor for both prevalent bacterial vaginosis and incident bacterial vaginosis.

Transition in the ages at key reproductive events and its determinants in India: evidence from NFHS 1992-93 to 2019-21.

INTRODUCTION: Reproductive health events have changed fertility and family planning needs, depicting the changing life patterns of women and the population to which they belong. Understanding the pattern at which these events occur helps in understanding the fertility pattern, family formation and the idea about health essential needs for women. This paper attempts to see the variation in reproductive events (first cohabitation, first sex and first birth) over three decades and also to see potential contributing factors among the reproductive age group of women using secondary data from Data Source: All rounds of the National Family Health Survey (1992-93 to 2019-2021) have been utilized. METHODS AND RESULTS: Cox Proportional Hazard Model illustrates that all regions have initiated their first birth later than women who belong to the east region similar pattern has been obtained for first cohabitation and first sex except for the central region. Multiple Classification Analysis (MCA) depicts the increasing pattern in the predicted mean age at first cohabitation, sex and birth for all demographic characteristics; the highest increment was found in SC women, Uneducated women and Muslim women. Kaplan Meier Curve demonstrates that women with no education, primary or secondary education are shifting towards higher educated women. Most importantly, the results of the multivariate decomposition analysis (MDA) revealed that education played the largest contribution among the compositional factors in the overall increase in mean ages at key reproductive events. CONCLUSIONS: Though reproductive health has long been essential in women's lives, they are still very confined to specific domains. Over time the government has formulated several proper legislative measures relating to various domains of reproductive events. However, given that the large size and heterogeneity in social and cultural norms result in changing ideas and choices regarding the initiation of reproductive events, national policy formulation needs to be improved or amended.

"Went Along With": Acquiescence During First Sexual Experience and Late-Life Health.

Working from a life course perspective, we examined how acquiescence (i.e., "lack of resistance") to an unwanted (i.e., "without experiencing a concomitant desire") first sexual experience was related to health and well-being in late life. Data were drawn from the second wave of the National Social Life, Health, and Aging Project (2010/11). The sample included 2558 older adults ages 62-99 (1182 men and 1376 women). Results from regression models suggested those respondents whose first sex was acquiesced reported higher levels of psychological distress and poorer physical health during late life than respondents whose first sex was wanted. Results from generalized structural equation modeling analysis further suggested that the association between acquiesced first sex and late-life health operated through adulthood socioeconomic status but not through marital relationships. We did not find gender differences in these processes.

Physical and Emotional Satisfaction at First Same-Sex Anal Sex in Young Gay and Bisexual Men.

Research has focused on adolescents' feelings about their first sexual experiences, but little research has examined this topic in sexual minority adolescents. In this study, we examined how experiencing emotional and physical satisfaction at first same-sex anal sex differed by age of first sex for young gay and bisexual men. We applied the time-varying effect model to data from an Internet survey of men who initiated first sex between ages 14-26 (n = 6401) to examine emotional and physical satisfaction at first same-sex anal sex across continuous age of onset and by partner factors. The majority of men reported satisfaction across all ages; however, satisfaction was generally less likely for men who had first anal sex with a non-relationship partner, an older partner, or a partner they had sex with only once and this was particularly true at earlier ages. Findings suggest that many young gay and bisexual men report satisfaction with their first anal sex and that relationship context can be important in predicting satisfaction, particularly at younger ages.

Parent, partner and individual contexts of very early first sex experiences among young men and their links to subsequent reproductive health outcomes.

Research indicates that upwards to 30% of US urban Black male adolescents report first sex younger than age 13; however, there is limited literature on the sexual and reproductive health outcomes and contexts of these early first sex experiences. This exploratory study described sexual and reproductive health histories and explored personal, partner and parent contextual factors associated with first sex experiences occurring at 13 years or younger among a sample of US urban young men aged 15-24. Participants were assessed on their demographics and sexual health histories and a subset of young men were assessed on the contextual factors related to their first sex experience. Pearson chi-squared tests examined factors associated with early first sex and Fisher's exact tests examined associated contextual factors. First sex at 13 years or younger was reported by 29% of young men. A higher proportion of young men who had first sex at 13 or younger than those who had sex onset at 14 or older reported having got someone pregnant, having a "much older" first partner, and relationship satisfaction with their mother (16%) and father (12%). Study findings highlight the need to better understand urban young men's early first sex experiences, including the support needed to promote their healthy sexual development.

Factors associated with age of first sex among women screened for an observational contraceptive vaginal ring study in Kisumu, Kenya, 2014.

Sex at an early age can have later life negative health outcomes. Insights on early sexual activity may help in the development of future health-promotion products and interventions related to pregnancy and sexually transmitted infections (STIs) prevention. Among Kenyan women participating in a contraceptive vaginal ring study, we determined: (1) the proportion with first sex at ≤15 years (early sex) and (2) factors associated with early sex. Baseline data collection and testing for pregnancy, STIs, and HIV were undertaken. A log-binomial or a modified Poisson regression was used to estimate univariable prevalence ratios and multivariable adjusted prevalence ratios (aPRs). Among 332 women aged 18-34 years, the median age of first sex was 16 years, with 40.1% experiencing early sex. Overall, 29.8% reported an older first sex partner (≥5 years); 83.9% indicated lack of readiness or intentions at first sex; and 56.2% received money, gifts, or favors as part of first sex. Early sex was more prevalent among inherited widows (a Luo cultural practice, aPR 1.49), gift recipients (aPR 1.38), women with a forced/unwanted sex history (aPR 1.42), or those with a partner of unknown or positive HIV status in the past 3 months (aPR 1.45). Sex before or at the age 15 may be associated with higher sexual risk behaviors. Complex power and gender relations may additionally influence exposure to sexual risk in our research setting.

Age at first marriage, age at first sex, family size preferences, contraception and change in fertility among women in Uganda: analysis of the 2006-2016 period.

BACKGROUND: Uganda's fertility was almost unchanging until the year 2006 when some reductions became visible. Compared to age at first marriage and contraceptive use, age at sexual debut and family size preferences are rarely examined in studies of fertility decline. In this study, we analyzed the contribution of age at first marriage, age at first sex, family size preferences and contraceptive use to change in fertility in Uganda between 2006 and 2016. METHODS: Using data from the 2006 and 2016 Uganda Demographic and Health Survey (UDHS), we applied a nonlinear multivariate decomposition technique to quantify the contribution of age at first marriage, age at first sex, family size preference and contraceptive use to the change in fertility observed during the 2006-2016 period. RESULTS: The findings indicate that 37 and 63% of the change in fertility observed between 2006 and 2016 was respectively associated with changing characteristics and changing fertility behavior of the women. Changes in proportion of women by; age at first marriage, age at first sex, family size preferences and contraceptive use were respectively associated with 20.6, 10.5 and 8.4% and 8.2% of the change in fertility but only fertility behavior resulting from age at first sex was significantly related to the change in fertility with a contribution of 43.5%. CONCLUSIONS: The study quantified the contribution of age at first marriage, age at first sex, family size preferences and contraceptive use to the change in fertility observed between 2006 and 2016. We highlight that of the four factors, only age at sexual debut made a significant contribution on the two components of the decomposition. There is need to address the low age at first sex, accessibility, demand for family planning services and youth-friendly family planning services to young unmarried women such that they can achieve their desired fertility. The contribution of other factors such as education attainment by women and place of residence and their relationship with changes in fertility calls for addressing if further reduction in fertility is to be realised.

Intimate partner violence, forced first sex and adverse pregnancy outcomes in a sample of Zimbabwean women accessing maternal and child health care.

BACKGROUND: Intimate partner violence (IPV) remains a serious problem with a wide range of health consequences including poor maternal and newborn health outcomes. We assessed the relationship between IPV, forced first sex (FFS) and maternal and newborn health outcomes. METHODS: A cross sectional study was conducted with 2042 women aged 15-49 years attending postnatal care at six clinics in Harare, Zimbabwe, 2011. Women were interviewed on IPV while maternal and newborn health data were abstracted from clinic records. We conducted logistic regression models to assess the relationship between forced first sex (FFS), IPV (lifetime, in the last 12 months and during pregnancy) and maternal and newborn health outcomes. RESULTS: Of the recent pregnancies 27.6% were not planned, 50.9% booked (registered for antenatal care) late and 5.6% never booked. A history of miscarriage was reported by 11.5%, and newborn death by 9.4% of the 2042 women while 8.6% of recent livebirths were low birth weight (LBW) babies. High prevalence of emotional (63,9%, 40.3%, 43.8%), physical (37.3%, 21.3%, 15.8%) and sexual (51.7%, 35.6%, 38.8%) IPV ever, 12 months before and during pregnancy were reported respectively. 15.7% reported forced first sex (FFS). Each form of lifetime IPV (emotional, physical, sexual, physical/sexual) was associated with a history of miscarrying (aOR ranges: 1.26-1.38), newborn death (aOR ranges: 1.13-2.05), and any negative maternal and newborn health outcome in their lifetime (aOR ranges: 1.32-1.55). FFS was associated with a history of a negative outcome (newborn death, miscarriage, stillbirth) (aOR1.45 95%CI: 1.06-1.98). IPV in the last 12 months before pregnancy was associated with unplanned pregnancy (aOR ranges 1.31-2.02) and booking late for antenatal care. Sexual IPV (aOR 2.09 CI1.31-3.34) and sexual/physical IPV (aOR2.13, 95%CI: 1.32-3.42) were associated with never booking for antenatal care. Only emotional IPV during pregnancy was associated with low birth weight (aOR1.78 95%CI1.26-2.52) in the recent pregnancy and any recent pregnancy negative outcomes including LBW, premature baby, emergency caesarean section (aOR1.38,95%CI:1.03-1.83). CONCLUSIONS: Forced first sex (FFS) and intimate partner violence (IPV) are associated with adverse maternal and newborn health outcomes. Strengthening primary and secondary violence prevention is required to improve pregnancy-related outcomes.

Trends in the age at reproductive transitions in the developing world: The role of education.

Girls' school participation has expanded considerably in the developing world over the last few decades, a phenomenon expected to have substantial consequences for reproductive behaviour. Using Demographic and Health Survey data from 43 countries, this paper examines trends and differentials in the mean ages at three critical life-cycle events for young women: first sexual intercourse, first marriage, and first birth. We measure the extent to which trends in the timing of these events are driven either by the changing educational composition of populations or by changes in behaviour within education groups. Mean ages have risen over time in all regions for all three events, except age at first sex in Latin America and the Caribbean. Results from a decomposition exercise indicate that increases in educational attainment, rather than trends within education groups, are primarily responsible for the overall trends. Possible explanations for these findings are discussed.

Social context and sexual intercourse among first-year students at selective colleges and universities in the United States.

Most examinations of sexual behavior ignore social context. Using panel data from the National Longitudinal Study of Freshmen, a panel study of 3924 students at 28 selective colleges and universities, I examine how institutional and peer-group characteristics influence the incidence of sexual intercourse among students during their freshman year. Students who enter college as virgins are more likely to have sexual intercourse on campuses where women comprise a higher proportion of the campus population and on campuses that are more academically rigorous. Students who had sex prior to college are less likely to have sex in college when campuses are more residential. Moreover, having friends who value religion and partying affects the likelihood that a student will have sex irrespective of their prior virginity status. These findings highlight the importance of social context for sexual behavior among college students and in the general population.

Age, quality, and context of first sex: associations with sexual difficulties.

INTRODUCTION: Research consistently indicates an association between a younger age at first sex and poorer sexual health outcomes. However, research addressing associations between age at first sex and sexual difficulties has produced mixed findings. Moreover, little is known about links between the context and quality of first sex and subsequent sexual difficulties. AIMS: The aims of this study are to examine whether (i) age and (ii) context and quality at first sex are associated with sexual difficulties; (iii) examine whether age at first sex and context and quality variables are independently associated (after mutual adjustment) with sexual difficulties; and (iv) examine whether age at first sex has an indirect effect on sexual difficulties through an effect on context or quality. METHODS: Data from 388 questionnaires were gathered from students aged 17-21 living in accommodation halls and by postal invitation to adults aged 25-35. MAIN OUTCOME MEASURES: The main outcome measure was the Golombok-Rust Inventory of Sexual Satisfaction (GRISS), which assesses sexual difficulties via an overall score and seven subscales. RESULTS: Appraising first sex as emotionally negative was associated with the majority of sexual difficulties. A less stable relationship at first sex was associated with sexual communication problems and dissatisfaction. Greater enjoyment and using substances were associated with a lower likelihood of anorgasmia for women. Age at first sex was directly associated with reduced sexual frequency only. A younger age at first sex was associated with a greater likelihood of negative appraisal and lower likelihood of a stable relationship and thereby indirectly associated with several sexual difficulties. CONCLUSIONS: Experiencing first sex as emotionally negative was consistently associated with later sexual difficulties. When attending to sexual difficulties, understanding the quality and context of first sex may be more useful than knowing the age at first sex. This research is limited by the retrospective nature of the reports of first sex.

Association between oral contraceptives and cervical cancer: A retrospective case-control study based on the National Health and Nutrition Examination Survey.

Background: Cervical cancer is the fourth most common cancer among females globally, with a high incidence and high mortality among females in developing countries. This retrospective case-control study aimed to investigate the association between oral contraceptives and cervical cancer, on which insufficient evidence still exists. Material and Methods: To examine the association between oral contraceptives and cervical cancer based on 7,496 females aged over 20 years from the National Health and Nutrition Examination Survey, multivariable logistic regression conducted from 1999 to 2016 was used. Results: Contraceptive use was positively associated with cervical cancer risk. In model 1 (unadjusted), a 195% increased risk of cervical cancer was observed among those who used oral contraceptives (odds ratio [OR] = 2.27, 95% confidence interval [CI] = 1.39-3.98, p = 0.002) compared to those who did not. In addition, the ORs for the exposed population were 1.74 (95% CI = 1.05-3.08, p = 0.041) and 1.93 (95% CI = 1.16-3.44, p = 0.017) in model 2 (adjusted for age, race, and body mass index [BMI]) and model 3 (adjusted for education level, ratio of family income to poverty, drinking status, smoking status, number of pregnancies, age at first sex, number of sexual partners, and whether to receive the human papillomavirus (HPV) vaccine in addition to model 2), respectively. Furthermore, subgroup analyses stratified by age, smoking status, BMI, age at first sex, number of sexual partners, and whether to receive the HPV vaccine also revealed that oral contraceptives were significantly associated with cervical cancer. Conclusion: This study demonstrated that oral contraceptive use increased the risk of cervical cancer. In addition, the higher risk, including individuals older than 45 years, having a high BMI (≥30 kg/m2), being current smokers, and having more than five sexual partners, may contribute to the development of cervical cancer.

Measuring sexual behavior among in-school youth in Rwanda: a cross-sectional analysis of self-reported timing of first sex and correlates of early sexual debut.

PURPOSE: Understanding the timing of sexual debut is critical for informing sexual and reproductive health interventions. We investigated sexual behavior and early sexual debut among Rwandan youth. METHODS: We conducted a cross-sectional analysis of data from a cluster-randomized trial with 6079 students ages 12-19 years in Rwanda. We examined predictors of early sexual debut (<15 years) using logistic regression to estimate odds ratios and factors associated with the timing of first sex using Cox models to estimate hazard ratios. Interpretations of sex were also explored. RESULTS: Participants were 15 years and 51.5% female on average; 1723 (28.3%) reported sexual activity. Among the 1320 participants who provided an age of sexual debut, 51.4% reported sex at ≤12 years and 75.7% at<15 years. Males had a higher odds of early sexual debut (adjusted odds ratio: 2.40; 95% CI: 1.99, 2.90) and a higher hazard of sex occuring at an earlier age than females (adjusted hazard ratio: 1.91; 95% CI: 1.67, 2.20). One-third of participants considered "sexual intercourse" to include kissing, touching, or masturbation. CONCLUSIONS: Sex at ≤12 years was frequently reported, indicating that interventions facilitating access to youth-friendly sexual and reproductive health services are necessary before age 12. Validation studies are needed to evaluate how interpretations of sexual intercourse influence the assessment of sexual activity. CLINICAL TRIAL: NCT04198272.

Genetic liability to age at first sex and birth in relation to cardiovascular diseases: a Mendelian randomization study.

BACKGROUND: Growing evidence suggests that various reproductive factors, including early menarche, early menopause, and age at first birth, may increase the risk of developing cardiovascular disease (CVD) later in life. However, the associations between reproductive factors and CVDs are inconsistent and controversial. Therefore, we conducted a two-sample Mendelian randomization (MR) analysis to explore the potential links between age at first sex (AFS) and age at first birth (AFB) and several CVDs. METHODS: We obtained summary statistics for exposure from the largest genome-wide association studies of AFS and AFB. To serve as instrumental variables, we selected 259 SNPs associated with AFS and 81 SNPs associated with AFB at the genome-wide significance level. We employed a random-effects inverse-variance weighted method to pool estimates, and conducted multivariable MR analysis to determine the direct association between AFS and AFB with CVDs, while accounting for the effects of confounders. RESULTS: The genetic liability to later AFS was associated with decreased risks of heart failure (odd ratio [OR] 0.700; 95% confidence interval [CI] 0.639-0.767; p = 2.23 × 10-14), coronary artery disease (OR 0.728; 95% CI 0.657-0.808; p = 1.82 × 10-9), myocardial infarction (OR 0.731; 95% CI 0.657-0.813; p = 8.33 × 10-9), stroke (OR 0.747; 95% CI 0.684-0.816; p = 6.89 × 10-11), and atrial fibrillation (OR 0.871; 95% CI 0.806-0.941; p = 4.48 × 10-4). The genetic liability to later AFB was also associated with decreased risks of CVDs, including myocardial infarction (OR 0.895; 95% CI 0.852-0.940; p = 8.66 × 10-6), coronary heart disease (OR 0.901; 95% CI 0.860-0.943; p = 9.02 × 10-6), heart failure (OR 0.925; 95% CI 0.891-0.961; p = 5.32 × 10-5), and atrial fibrillation (OR 0.944; 95% CI 0.911-0.978; p = 0.001). However, no association was found between AFB and stroke. The associations remained independent from the effects of AFS and AFB on potential confounders, including smoking, alcohol intake, body mass index, and depression. Mediation analysis suggested that education attainment partly mediates the link from AFS and AFB to CVD outcomes. CONCLUSION: Our results observed a causal relationship between later AFS, AFB and lower CVDs risk; it emphasizes the importance of providing sex education since early sex and birth may have undesirable effects. Cardiovascular risk stratification that considers reproductive factors may help address CVD risk.

Reproductive characteristics of the hermaphroditic four-finger threadfin, Eleutheronema tetradactylum (Shaw, 1804), in tropical coastal waters.

This study investigated the reproductive traits of the hermaphroditic four-finger threadfin, Eleutheronema tetradactylum, along the coasts of Thailand during January to December 2021. Fish samples were collected from Pattani Bay, Thailand to assess the sex ratio, gonadosomatic index (GSI), maturity stage and fecundity. Additional fish samples were also collected from other areas to evaluate the length and weight at first sex change (Ls50 and Ws50) and length at first maturity (Lm50). The overall sex ratio for male and female was 1:0.69 with male being predominant throughout the year. Threadfin fish spawn the whole year round with peaks during moderate rainy and heavy rainy seasons. Histological examination confirmed its protandrous hermaphrodite posing multiple spawning habits. The average fecundity was 1.85 × 105 ± 1.05 × 105 eggs and positively related with standard length, body weight, gonad weight, and egg diameter (p < 0.05). The Ls50 and Ws50 were 27.58 cm and 419.39 g, and 29.71 cm and 457.28 g, for fish from Pattani Bay and Samut Prakan province, respectively. The Lm50 of male from Pattani Bay and Samut Prakan province were 25.78 cm and 25.56 cm, respectively, which were larger than those from Satun and Nakhon Sri Thammarat provinces. The Lm50 of females from Pattani Bay was smaller than that from Samut Prakan province. This study provided fundamental information on the reproductive characteristics of E. tetradactylum, which can be implemented to support management of natural fish stock and aquaculture development.

Adolescent Girls and Young Women in Kenya Demonstrate Rapid STI Incidence Following First Sex: Data From a Longitudinal Cohort.

PURPOSE: Adolescent girls and young women (AGYW) are disproportionately affected by STIs. Observation of life course events can describe behavioral and biological factors associated with STI risk. METHODS: Sexually inexperienced AGYW aged 16-20 years in Kenya were followed for five years. Quarterly visits assessed for C. trachomatis (CT), N. gonorrhea (GC), and T. vaginalis (TV), bacterial vaginosis (BV), HSV-2, and HIV. Sexual activity was self-reported but amended if incongruent with results from STI, pregnancy, or any other testing. Cox regression and Generalized Estimating Equation models were used to determine hazard ratios (HRs) and relative risks (RRs) of STI. RESULTS: During follow-up, 293 of 400 participants reported sex, 163 AGYW experienced an STI, and 72 participants had multiple STIs. Among 163 participants that experienced an STI, there were a total of 259 visits where STIs were detected, 78% (n = 201) of which included CT. Cox regression found participants with BV had over two-fold higher risk of first STI acquisition (adjusted hazard ratio (aHR): 2.35; 95% confidence interval (CI) 1.43-3.88; p = .001). Increased risk for first STI episode was associated with a new partner (aHR: 3.16; 95% CI 1.59-6.28; p = .001). AGYW who did not disclose sexual activity had the highest risk (aHR: 3.60; 95% CI 1.93-6.70; p < .001). Condom use was low, with 21% reporting condom use with sex. GEE analysis of all STIs including incident, prevalent, and recurrent, confirmed these risk factors. DISCUSSION: During the critical years after first sex, AGYW with BV, new sexual partners, and those who did not disclose sexual activity were at highest risk for STI events, especially CT.

Adolescent Reproductive Health Outcomes Among Mexican-Origin Women on Both Sides of the U.S.-Mexico Border.

PURPOSE: Much reproductive health research on the Latina population overlooks heterogeneity by national origin, nativity, and age and also ignores how U.S.-based populations differ from those in "sending" nations. The purpose of this study is to describe a history of adolescent birth, age at first sex, and contraceptive use at first sex in the Mexican-origin population in both the United States and Mexico. METHODS: We developed a binational dataset merging two comparable nationally representative cross-sectional surveys in the United States and Mexico and used covariate balancing propensity scores to balance the age structure of our four samples: U.S.-born Latinas of Mexican origin, foreign-born Latinas of Mexican origin, U.S.-born non-Latina Whites, and Mexican women residing in Mexico. We used a negative binomial regression and calculated the predicted probability of experiencing at least one adolescent birth for each ethnicity/nativity group, stratified by 5-year age group. We also described age and contraceptive use at first sex. RESULTS: Foreign-born Latinas of Mexican origin and Mexicans in Mexico had similar adjusted probabilities of reporting an adolescent birth (30.1% and 29.9%, respectively), which were higher than those of Mexican-Americans (26.2%) and U.S.-born non-Latina Whites (11.6%). History of an adolescent birth is declining across all four groups among younger ages. Differences do not appear to be driven by the timing of first sex but by contraceptive use, which is increasing among younger age groups. DISCUSSION: Access to and use of effective contraception rather than timing of initiation of sexual activity is a key determinant of U.S. Latina and Mexican adolescent births.

A model for reconstructing trends and distribution in age at first sex from multiple household surveys with reporting biases.

Age at first sex (AFS) is a key indicator for monitoring sexual behaviour risk for HIV and other sexually transmitted infections. Reporting of AFS data, however, suffers social-desirability and recall biases which obscure AFS trends and inferences from the data. We illustrated AFS reporting biases using data from nationally-representative Demographic and Health Surveys conducted between 1992 and 2019 in Ethiopia, Guinea, Senegal, and Zambia. Based on this, we proposed a time-to-event, interval censored model for the distribution of AFS that uses overlapping reports by the same birth cohort in successive surveys to adjust for reporting biases. The three-parameter log-skew-logistic distribution described the asymmetric and nonmonotonic hazard exhibited by empirical AFS data. In cross-validation analysis, incorporating a term for reporting bias as a function of age at report improved model predictions for the trend in AFS over birth cohorts. In the four example applications, the quartiles of the AFS distribution were 16-23 years for Ethiopian and Senegalese women and 15-20 years for Guinean and Zambian men. Median AFS increased by around one to 1.5 years between the 1960 and 1989 birth cohorts for all four datasets. During adolescent and young adult ages, men tended to report an earlier AFS while women tended to report an older AFS than when asked in their late twenties. Above age 30, both male and female respondents tended to report older AFS compared to when surveyed in their late twenties. Simulations validated that the model recovered the trend in AFS in the presence of reporting biases. When there were biases, at least three surveys were needed to obtain reliable estimate for a 20-year trend. Mis-specified reference age at which AFS reporting is assumed unbiased did not affect the trend estimate but resulted in biased median AFS in the most recent birth cohorts.

The State of Adolescent Sexual and Reproductive Health.

In the 25 years since the 1994 International Conference on Population and Development, significant progress has been made in adolescent sexual and reproductive health and rights (ASRHR). Trend analysis of key ASRHR indicators at global, national, and subnational levels indicates that adolescent girls today are more likely to marry later, delay their first sexual experience, and delay their first childbirth, compared with 25 years ago; they are also more likely to use contraceptives. Despite overall progress, however, unequal progress in many ASRHR outcomes is evident both within and between countries, and in some locations, the state of adolescents' lives has worsened. Population growth in countries with some of the worst shortfalls in ASRHR mean that declining rates, of child marriage, for example, coexist with higher absolute numbers of girls affected, compared with 25 years ago. Emerging trends that warrant closer attention include increasing rates of ovarian and breast cancer among adolescent girls and sharp increases in the proportion of adolescents who are overweight or obese, which has long-term health implications.