Effectiveness of female and male condoms in preventing exposure to semen during vaginal intercourse: a randomized trial

Reversible female contraceptives: historical, current, and future perspectives†

Contraception is a practice with extensive and complicated social and scientific histories. From cycle tracking, to the very first prescription contraceptive pill, to now having over-the-counter contraceptives on demand, family planning is an aspect of healthcare that has undergone and will continue to undergo several transformations through time. This review provides a comprehensive overview of current reversible hormonal and non-hormonal birth control methods as well as their mechanism of action, safety, and effectiveness specifically for individuals who can become pregnant. Additionally, we discuss the latest Food and Drug Administration (FDA)-approved hormonal method containing estetrol and drospirenone that has not yet been used worldwide as well as the first FDA-approved hormonal over-the-counter progestin-only pills. We also review available data on novel hormonal delivery through microchip, microneedle, and the latest FDA-approved non-hormonal methods such as vaginal pH regulators. Finally, this review will assist in advancing female contraceptive method development by underlining constructive directions for future pursuits. Information was gathered from the NCBI and Google Scholars databases using English and included publications from 1900 to present. Search terms included contraceptive names as well as efficacy, safety, and mechanism of action. In summary, we suggest that investigators consider the side effects and acceptability together with the efficacy of contraceptive candidate towards their development.

Factors Associated with Condom Use Among Out-of-School Young People on Anti-Retroviral Therapy in Central Uganda

Introduction

Methods

Results

Conclusion

Semen: A modulator of female genital tract inflammation and a vector for HIV-1 transmission

In order to establish productive infection in women, HIV must transverse the vaginal epithelium and gain access to local target cells. Genital inflammation contributes to the availability of HIV susceptible cells at the female genital mucosa and is associated with higher HIV transmission rates in women. Factors that contribute to genital inflammation may subsequently increase the risk of HIV infection in women. Semen is a highly immunomodulatory fluid containing several bioactive molecules with the potential to influence inflammation and immune activation at the female genital tract. In addition to its role as a vector for HIV transmission, semen induces profound mucosal changes to prime the female reproductive tract for conception. Still, most studies of mucosal immunity are conducted in the absence of semen or without considering its immune impact on the female genital tract. This review discusses the various mechanisms by which semen exposure may influence female genital inflammation and highlights the importance of routine screening for semen biomarkers in vaginal specimens to account for its impact on genital inflammation.

Perceived male partner attitudes toward the female condom predict female university students' use of the female condom

Female and male condoms are the only methods that prevent both sexually transmitted infections (STIs), including HIV, and unintended pregnancy. Despite continuing high STI rates, few studies investigate factors predicting whether women initiating female condom (FC) use sustain use. Using data from a randomized trial, we examined predictors of sustained FC use at five-month follow-up (FU2) among female university students in South Africa who participated in either a one-session, information-only, group-delivered Minimal Intervention or a two-session, group-delivered Enhanced Intervention. In the final multiple logistic regression model, believing one's partner holds positive attitudes toward the FC (aOR = 1.40; p = 0.028), and greater FC use for vaginal sex at previous assessment (aOR) = 1.19; p = 0.008) were associated with greater odds of FC use at FU2. Excluding number of FC-protected occasions at FU1 from the analysis, discussing FC use with partner (aOR = 2.89; p = 0.071) and believing one's partner holds positive attitudes toward the FC (aOR = 1.63; p < 0.001) were associated with greater odds of use at FU2. The FC empowers women to protect themselves from both STIs and unintended pregnancy, but targeted interventions are needed to address men's negative attitudes toward the device. Engaging men as FC champions to support and promote FC use, along with marketing campaigns targeted to men, may expand FC coverage and enhance uptake.

Effectiveness of the female condom in preventing HIV and sexually transmitted infections: a systematic review and meta-analysis

BACKGROUND

The effectiveness of female condoms for preventing HIV and sexually transmitted infections (STIs) remains inconclusive. We examined the effects of female condoms on the acquisition of HIV and STIs.

METHODS

We searched four databases, two trial registries, and reference lists of relevant publications in October 2018 and updated our search in February 2020. We screened search output, evaluated study eligibility, and extracted data in duplicate; resolving differences through discussion. We calculated the effective sample size of cluster randomised trials using an intra-cluster correlation coefficient of 0·03. Data from similar studies were combined in a meta-analysis. We performed a non-inferiority analysis of new condoms relative to marketed ones using a non-inferiority margin of 3%. We assessed the certainty of evidence using GRADE.

RESULTS

We included fifteen studies of 6921 women. We found that polyurethane female condoms (FC1) plus male condoms may be as effective as male condoms only in reducing HIV acquisition (1 trial, n = 149 women, RR 0.07, 95%CI 0.00-1.38; low-certainty evidence). However, the use of FC1 plus male condoms is superior to male condoms alone in reducing the acquisition of gonorrhoea (2 trials, n = 790, RR 0.59, 95%CI 0.41-0.86; high-certainty evidence) and chlamydia (2 trials, n = 790, RR 0.67, 95%CI 0.47-0.94; high-certainty evidence). Adverse events and failure rates of FC1 were very low and decreased during follow up. Although the functionality of newer female condoms (Woman's, Cupid, Pheonurse, Velvet, and Reddy) may be non-inferior to FC2, there were no available studies assessing their efficacy in preventing HIV and STIs.

CONCLUSION

The use of female plus male condoms is more effective than use of male condoms only in preventing STIs and may be as effective as the male condom only in preventing HIV. There is a need for well conducted studies assessing the effects of newer female condoms on HIV and STIs.

PROSPERO REGISTRATION NUMBER

CRD42018090710.

Comparison of self-reported female condom failure and biomarker-confirmed semen exposure

OBJECTIVE

To investigate whether rates of self-reported Woman's Condom (WC) clinical failure and semen exposure from a functionality study are comparable to results from a contraceptive efficacy substudy.

STUDY DESIGN

We structured our comparative analysis to assess whether functionality studies might credibly supplant contraceptive efficacy studies when evaluating new female condom products. Couples not at risk of pregnancy in the functionality (breakage/slippage/invagination/penile misdirection) study and women in the contraceptive efficacy study completed condom self-reports and collected precoital and postcoital vaginal samples for up to four uses of the WC. Both studies used nearly identical self-report questions and the same self-sampling procedures and laboratory for prostatic specific antigen (PSA), a well-studied semen biomarker. We compared condom failure and semen exposure proportions using generalized estimating equations methods accounting for within-couple correlation.

RESULTS

Ninety-five (95) efficacy substudy participants used 334 WC and 408 functionality participants used 1572 WC. Based on self-report, 19.2% WC (64 condoms) clinically failed in the efficacy substudy compared to 12.3% WC (194 condoms) in the functionality study (p=.03). Of the 207 WC efficacy uses with evaluable postcoital PSA levels, 14.5% (30 uses) resulted in semen exposure compared to 14.2% (184 uses) of the 1293 evaluable WC functionality study uses.

CONCLUSIONS

When evaluating the ability of an experimental condom to prevent semen exposure, the rate of clinical condom failure reported by participants risking pregnancy in an efficacy substudy was significantly higher than the rate reported by participants not risking pregnancy in a functionality study. The rate of semen exposure, assessed by an objective biomarker was nearly identical for the two studies.

IMPLICATIONS

Our results suggest that an objective marker of semen exposure in functionality studies could provide a reasonable alternative to contraceptive efficacy studies in evaluating risk of unintended pregnancy and inferring protection from sexually transmitted infection than condom failure rates based on self-report.

Awareness and utilization of female condoms among street youths in Ibadan, an urban setting in South-West Nigeria

INTRODUCTION

Female condom awareness and use have been poorly documented in sub-Saharan region especially among street youths. This study assessed its awareness and use among street youths.

METHODS

A cross-sectional study was conducted among 964 youths between ages 15 to 24 years old using questionnaires to elicit information. Univariate and multivariate analysis were conducted at 5% level of significance.

RESULTS

More than half (69.9%) were males and between 20-25 years of age (61.2%). More than three-quarter (81.0%) had initiated sexual activity. Almost half (47.9%) of the respondents have heard about female condoms however only 16.8% have ever seen while 4.3% have actually ever used a female condom. Age, education, current sexual activity and experience of rape attempt were predictors of female condom awareness.

CONCLUSION

Awareness of female condom was a significant predictor of utilization of female condoms. There is therefore a need for proper awareness and education on the effectiveness of female condoms.

Prostate-specific antigen concentration in vaginal fluid after exposure to semen

OBJECTIVE

Prostate-specific antigen (PSA) is the best established biomarker of semen exposure. PSA in vaginal fluid returns to pre-exposure concentrations within 24-48 h, but the speed of decay during the first 10 h is unknown. We sought to determine how fast PSA concentrations decline during the first 10 h after exposure to semen.

STUDY DESIGN

Women in the 50 enrolled couples were intravaginally inoculated with 10, 20, 100 and 200 μl of their partner's semen and then collected vaginal swabs immediately after, 30 min, 4 h and 10 h after exposure. Forty-seven sets of samples were tested for PSA. Mixed linear models for repeated measures examined the association between log-transformed PSA values and sampling time and semen exposure volume. Sensitivity analyses excluded data from nonabstainers. Fixed-effect estimates from the statistical models were graphed.

RESULTS

PSA values were highest at 200 μl inoculation volumes and at earlier post-exposure time points, then decline steadily. The lowest inoculation volume (10 μl) corresponded to the smallest concentration of PSA throughout the post-inoculation time points. Average PSA levels return to clinically non-detectable levels within 10 h only at the lowest semen exposures. The PSA decay curve assumes a very similar profile across all time points and semen amounts.

CONCLUSIONS

The PSA decay curve is similar for varying semen exposure volumes, with average PSA concentrations remaining above clinical thresholds 10 h after exposure at all except the very smallest semen exposure levels. PSA is an objective marker of recent exposure to semen, permitting such detection with high accuracy.

IMPLICATIONS

This study clarifies how PSA values vary at different semen exposure levels and time points during the first 10 h post-exposure. Future contraceptive studies that use PSA as a semen biomarker will be better informed about PSA concentrations at different sampling times and exposure amounts.

Assessment of the vaginal residence time of biomarkers of semen exposure

OBJECTIVE

The primary objective of this pilot study is to determine and compare the residence time in the vagina of biomarkers of semen exposure for up to 15 days post exposure. The biomarkers are prostate-specific antigen (PSA), Y chromosome DNA, the sex determining region of the Y chromosome (SRY) and testis-specific protein Y-encoded 4 (TSPY4). The secondary objectives are to determine if biomarker concentrations differed between intercourse and inoculation groups, to establish whether the sampling frequency post exposure affected biomarker concentrations and decay profile and to determine if biomarker concentrations in vaginal swabs obtained by the participant at home were similar to swabs obtained by the nurse in the clinic.

STUDY DESIGN

We randomized healthy women to unprotected intercourse (n=17) versus vaginal inoculation with the male partner's semen in the clinic (n=16). Women were then further randomized to have vaginal swabs obtained at either 7 or 4 time points after semen exposure, up to 15 days post exposure, either obtained at home by the participant or in the clinic by the research nurse.

RESULTS

PSA and SRY were markers of recent semen exposure. TSPY4 was detectable in approximately 50% of participants at 15 days post exposure. Unprotected intercourse resulted in significantly higher concentrations of select biomarkers. Sampling frequency and home versus clinic sampling had no significant effect on biomarker concentrations.

CONCLUSIONS

Objective biomarkers of recent or distant semen exposure may have great utility for verifying protocol compliance in a variety of clinical trials.

Knowledge, attitudes, practices and behaviors associated with female condoms in developing countries: a scoping review

Women in developing countries are at high risk of HIV, sexually transmitted infections, and unplanned pregnancy. The female condom (FC) is an effective dual protective method regarded as a tool for woman’s empowerment, yet supply and uptake are limited. Numerous individual, socioeconomic, and cultural factors influence uptake of new contraceptive methods. We reviewed studies of FC knowledge, attitudes, practices, and behaviors across developing countries, as well as available country-level survey data, in order to identify overarching trends and themes. High acceptability was documented in studies conducted in diverse settings among male and female FC users, with FCs frequently compared favorably to male condoms. Furthermore, FC introduction has been shown to increase the proportion of “protected” sex acts in study populations, by offering couples additional choice. However, available national survey data showed low uptake with no strong association with method awareness, as well as inconsistent patterns of use between countries. We identified a large number of method attributes and contextual factors influencing FC use/nonuse, most of which were perceived both positively and negatively by different groups and between settings. Male partner objection was the most pervasive factor preventing initial and continued use. Importantly, most problems could be overcome with practice and adequate support. These findings demonstrate the importance of accounting for contextual factors impacting demand in FC programming at a local level. Ongoing access to counseling for initial FC users and adopters is likely to play a critical role in successful introduction.

Barrier methods for human immunodeficiency virus prevention

Condoms remain the most effective barrier against the sexual transmission of the human immunodeficiency virus (HIV). Male condoms have proven to be 80% to 90% effective, and female condoms have similar results. Poor adherence and improper use limit their effectiveness. In addition to condoms, microbicides are a promising barrier against HIV transmission. More than 50 candidate topical microbicide compounds have undergone preclinical or clinical testing in the last 10 years, but there are currently no US Food and Drug Administration (FDA)-approved compounds. Rectal microbicides are also being developed, as anal receptive sex is an effective mode of HIV transmission.

Biological markers of sexual activity: tools for improving measurement in HIV/sexually transmitted infection prevention research

Research on interventions to prevent HIV and other sexually transmitted infections (STIs) is heavily influenced by participant reporting of sexual behavior, despite uncertainty about its validity. Exclusive reliance on participant self-report often is based, overtly or by implication, on 4 assumptions: (1) no feasible alternatives exist; (2) misreporting can be minimized to levels that can be disregarded; (3) misreporting tends to underreport sensitive behaviors; and (4) misreporting tends to be nondifferential with respect to the groups being compared. The objective of this review are to evaluate these assumptions, including a review of studies using semen biomarkers to evaluate the validity of self-reported data, and to make recommendations for applying biological markers of semen exposure detectable in women to further strengthen research on HIV/STI prevention. Increasing evidence shows that semen biomarkers provide an important means of assessing and augmenting the validity of studies on HIV/STI prevention. Additional biomarkers are needed to assess male exposure to vaginal sex and both male and female exposure to anal sex. Methods and study designs that incorporate biomarkers into studies collecting self-reported behavioral data should be considered where possible.

Detection of two biological markers of intercourse: prostate-specific antigen and Y-chromosomal DNA

BACKGROUND

Although biological markers of women's exposure to semen from vaginal intercourse have been developed as surrogates for risk of infection or probability of pregnancy, data on their persistence time and clearance are limited.

STUDY DESIGN

During 2006-2008, 52 couples were enrolled for three 14-day cycles of abstinence from vaginal sex during which women were exposed in the clinic to a specific quantity (10, 100 or 1000 μL) of their partner's semen. Vaginal swabs were collected before and at 1, 6, 12, 24, 48, 72 and 144 h after exposure for testing for prostate-specific antigen (PSA) and Y-chromosome DNA (Yc DNA).

RESULTS

Immediately after exposure to 1000 μL of semen, the predicted sensitivity of being PSA positive was 0.96; this decreased to 0.65, 0.44, 0.21 and 0.07 at 6, 12, 24 and 48 h, respectively. Corresponding predicted sensitivity of being Yc DNA positive was 0.72 immediately postexposure; this increased to 0.76 at 1 h postexposure and then decreased to 0.60 (at 6 h), 0.63 (at 12 h), 0.49 (at 24 h), 0.21 (at 48 h), 0.17 (at 72 h) and 0.12 (at 144 h).

CONCLUSIONS

Overall findings suggest that PSA may be more consistent as a marker of very recent exposure and that Yc DNA is more likely to be detected in the vagina after 12 h postexposure compared to PSA.

Translation of biomedical prevention strategies for HIV: prospects and pitfalls

Early achievements in biomedical approaches for HIV prevention included physical barriers (condoms), clean injection equipment (both for medical use and for injection drug users), blood and blood product safety, and prevention of mother-to-child transmission. In recent years, antiretroviral drugs to reduce the risk of transmission (when the infected person takes the medicines; treatment as prevention) or reduce the risk of acquisition (when the seronegative person takes them; preexposure prophylaxis) have proven to be efficacious. Circumcision of men has also been a major tool relevant for higher prevalence regions such as sub-Saharan Africa. Well-established prevention strategies in the control of sexually transmitted diseases and tuberculosis are highly relevant for HIV (ie, screening, linkage to care, early treatment, and contact tracing). Unfortunately, only slow progress is being made in some available HIV-prevention strategies such as family planning for HIV-infected women who do not want more children and prevention of mother-to-child HIV transmission. Current studies seek to integrate strategies into approaches that combine biomedical, behavioral, and structural methods to achieve prevention synergies. This review identifies the major biomedical approaches demonstrated to be efficacious that are now available. We also highlight the need for behavioral risk reduction and adherence as essential components of any biomedical approach.

Structural issues affecting creation of a community action and advocacy board

The most effective woman-initiated method to prevent HIV/sexually transmitted infections is the female condom (FC). Yet, FCs are often difficult to find and denigrated or ignored by community health and service providers. Evidence increasingly supports the need to develop and test theoretically driven, multilevel interventions using a community-empowerment framework to promote FCs in a sustained way. We conducted a study in a midsized northeastern US city (2009-2013) designed to create, mobilize and build capacity of a community group to develop and implement multilevel interventions to increase availability, accessibility and support for FCs in their city. The Community Action and Advocacy Board (CAAB) designed and piloted interventions concurrently targeting community, organizational and individual levels. Ethnographic observation of the CAAB training and intervention planning and pilot implementation sessions documented the process, preliminary successes, challenges and limitations of this model. The CAAB demonstrated ability to conceptualize, plan and initiate multilevel community change. However, challenges in group decision-making and limitations in members' availability or personal capacity constrained CAAB processes and intervention implementation. Lessons from this experience could inform similar efforts to mobilize, engage and build capacity of community coalitions to increase access to and support for FCs and other novel effective prevention options for at-risk women.

Randomized controlled trial on the effectiveness of counseling messages for avoiding unprotected sexual intercourse during sexually transmitted infection and reproductive tract infection treatment among female sexually transmitted infection clinic patients

BACKGROUND

The effectiveness of counseling messages to avoid unprotected sex during short-term treatment for curable sexually transmitted infections is unknown.

METHODS

We randomized 300 female STI clinic patients 18 years or older with cervicitis and/or vaginal discharge in Kingston, Jamaica, in 2010 to 2011, to 1 of 2 counseling messages for their course of syndromic treatment: abstinence only or abstinence backed up by condom use. At a follow-up visit 6 days afterward, we collected vaginal swabs to test for prostate-specific antigen (PSA), a biological marker of recent semen exposure, and administered a questionnaire assessing sexual behavior.

RESULTS

No differences were found in the proportions of women testing positive for PSA at follow-up in the abstinence-plus-condom group (11.9%) and abstinence-only group (8.4%) (risk difference, 3.5; 95% confidence interval, -3.5 to 10.5). There also was no significant difference in reporting of unprotected sex between groups. Reporting a history of condom use before enrollment significantly modified the effect of counseling arm on PSA positivity (P = 0.03). Among those reporting recent condom use, 10.3% in the abstinence-only arm and 4.8% in the abstinence-plus-condom arm tested positive for PSA. Conversely, among those not reporting recent condom use, 6.5% in the abstinence-only arm and 17.3% in the abstinence-plus-condom arm had PSA detected.

CONCLUSIONS

We found no evidence to support the superiority of either counseling message. Post hoc analyses suggest that women with recent condom experience may benefit significantly more from abstinence-plus-condom messages, whereas women without such experience may benefit significantly more from abstinence-only messages. Providers should weigh individual condom use history when determining the most appropriate counseling message.

Initial and sustained female condom use among low-income urban U.S. women

OBJECTIVES

The female condom (FC), an effective barrier method for HIV/sexually transmitted infection (STI) prevention, continues to be absent from most community settings, including reproductive health and treatment clinics. Reducing or eliminating basic barriers, including lack of awareness, knowledge of proper use, and access to free samples, may significantly increase use among those who want or need them.

METHODS

A prospective cohort of 461 women in Hartford, Connecticut (2005-2008), was interviewed at baseline, 1 month, and 10 months about FC use and other personal, partner, peer, and community factors. All participants received brief demonstration of FC use and four free FC1 at baseline. Pairwise longitudinal tests and structural equation modeling were used to test predictors of initial (1 month) and sustained (10 month) FC use.

RESULTS

Although only 29% of the sample reported ever having used FC at baseline, 73% of never users (51% of the returned 1-month sample) had initiated FC use by 1 month after receiving the brief intervention. Additionally, 24% of the returned 10-month sample (30% of 10-month FC users) reported sustained use, measured as having used FC at baseline or 1 month and also in the prior 30 days. General latent variable modeling indicated that FC knowledge and attitudes predicted initiating FC use; male condom use, FC knowledge and attitudes, and network exposure to FC information predicted sustained use.

CONCLUSIONS

Findings indicated that many women will potentially initiate and continue using FC when basic barriers are removed. Brief FC education with free trial samples should be built into standard clinical practice and public health programs.

Effect of topical vaginal products on the detection of prostate-specific antigen, a biomarker of semen exposure, using ABAcards

BACKGROUND

Prostate-specific antigen (PSA) is a biomarker of recent semen exposure. There is currently only limited information on whether topical vaginal products affect PSA assays. We investigated this question using various dilutions of several vaginal products (lubricants and spermicides) and the Abacus ABAcard for PSA detection.

STUDY DESIGN

Pooled semen controls and various dilutions of nonoxynol-9 (N9), carboxymethyl cellulose (CMC), Replens, Gynol 2, K-Y jelly, Astroglide, Surgilube, combined with pooled semen dilutions, were tested for PSA using the Abacus ABAcard.

RESULTS

N9 (2% with saline) and CMC did not appear to affect the results of testing with the ABAcard, but not all semen dilutions were tested. The other products (including Replens and Gynol, which is 2% N9 with propylene glycol, K-Y, Astroglide and Surgilube) at some of the dilutions tested either affected or gave invalid results with PSA testing using the ABAcard. Both Gynol 2 and K-Y at 1:10 dilution gave false-positive results.

CONCLUSIONS

Some vaginal products affect PSA results obtained by using the semiquantitative ABAcard. In vivo confirmation is necessary to further optimize PSA detection when topical vaginal products are present.

Optimal methods for collecting and storing vaginal specimens for prostate-specific antigen testing in research studies

BACKGROUND

Prostate-specific antigen (PSA) detected in vaginal fluid can be used in studies of HIV/sexually transmitted infection (STI) and pregnancy prevention as an alternative to relying on participant reports of exposure to semen. Optimal methods for collecting and storing specimens for this testing have not been determined.

STUDY DESIGN

We conducted a controlled, in vitro experiment of 550 specimens spiked with semen to determine the effects of swab type (five types), storage conditions of the swabs (room temperature with or without desiccant or at -80°C without desiccant) and time from collection to testing (seven intervals over the course of 12 months) on the identification of PSA. We performed factorial analysis of variance to identify factors influencing PSA detection.

RESULTS

Concentrations of PSA detected in the swabs declined with time of storage over the 1-year experiment (p<.01). The 1-mL, rayon-tipped swab stored immediately at -80°C following collection performed best.

CONCLUSIONS

If immediate testing or freezer storage is not feasible, investigators should use a swab with 1-mL capacity with processing and testing as soon as possible after specimen collection.

Behavioral and biomedical combination strategies for HIV prevention

Around 2.5 million people become infected with HIV each year. This extraordinary toll on human life and public health worldwide will only be reversed with effective prevention. What's more, in the next few years, it is likely at least, that no single prevention strategy will be sufficient to contain the spread of the disease. There is a need for combination prevention as there is for combination treatment, including biomedical, behavioral, and structural interventions. Expanded HIV prevention must be grounded in a systematic analysis of the epidemic's dynamics in local contexts. Although 85% of HIV is transmitted sexually, effective combinations of prevention have been shown for people who inject drugs. Combination prevention should be based on scientifically derived evidence, with input and engagement from local communities that fosters the successful integration of care and treatment.

Condom type may influence sexual behavior and ejaculation and complicate the assessment of condom functionality

BACKGROUND

Studies that evaluate condom effectiveness are affected by factors related to how the condom was used, and these factors may not be consistent between different types of condoms. Also, subjective assessments of the sexual act may be unreliable.

STUDY DESIGN

We performed a secondary data analysis of a randomized crossover trial of male and female condoms among 108 couples.

RESULTS

Self-reported duration and activeness of coital acts were significantly different for uses of the male condom compared to uses of the female condom. Fewer individuals reported ejaculation occurring with the female condom. Reliability of self-reports of ejaculation compared to a biological marker of semen detected inside the used male and female condoms was not strong.

CONCLUSIONS

We found that sexual behaviors appear to differ by the type of condom used for the coital act. Studies should consider sexual behavior when evaluating condom effectiveness. Furthermore, studies would be strengthened by the use of a biological marker of semen to determine whether ejaculation, and therefore a true risk of exposure, occurred.

Prostate-specific antigen as a biomarker of condom failure: comparison of three laboratory assays and self-reported condom use problems in a randomized trial of female condom performance

BACKGROUND

Prostate-specific antigen (PSA), a biomarker for semen exposure, may provide a more objective measure of condom failure than subject self-reports. Methods for measuring PSA vary and their comparability with respect to assessing condom performance has not been adequately evaluated. This study compared results from three different PSA assays of vaginal samples collected by subjects in a randomized clinical trial which compared the performance of female condoms.

STUDY DESIGN

We selected 30 pairs of pre- and post-coital vaginal samples from subjects who reported condom functionality problems or whose original PSA assay was positive. Samples were retested using three different PSA assays [quantitative enzyme-linked immunoassay (EIA), rocket immune-electrophoresis (RIE) and chromatographic immunoassay (CIA)]. We compared the proportion of condom uses where the post-coital PSA result indicated semen exposure for each of the three assays.

RESULTS

Despite varying levels of sensitivity, the results from all three assays were remarkably consistent. Self-reported condom failures did not correlate well with positive PSA results, suggesting that exclusive reliance on either PSA or user self-report may be inadequate for assessing condom functionality.

CONCLUSION

In combination with user self-report of condom failure, PSA testing provides a reliable, objective marker of condom functionality. Studies based on PSA testing may improve on conventional contraceptive clinical trials by offering a more direct assessment of a condom product's ability to prevent semen exposure.

A review of the effectiveness and acceptability of the female condom for dual protection

The female condom remains the sole female-initiated method of dual protection against unintended pregnancy and sexually transmissible infections (STIs), including HIV. We reviewed published data on the effectiveness and acceptability of the female condom for protection against pregnancy and infection. Overall, use of the female condom is low and several barriers hinder the wider adoption of the use of the method. Research on effectiveness has focussed on pregnancy, STIs and biological markers of semen exposure. Although the data available suggest that female condoms (or a mixture of female and male condoms) may provide similar degrees of protection against pregnancy and STIs as do latex male condoms alone, this conclusion has not been demonstrated and thus comparative research is urgently needed.

Do women using long-acting reversible contraception reduce condom use? A novel study design incorporating semen biomarkers

Long-acting reversible contraceptive (LARC) methods are highly effective against pregnancy. A barrier to their widespread promotion can include the concern they will lead reduced condom use and, thus, will put couples at higher risk for sexually transmitted infections (STIs). We review evidence from previous studies of condom "migration" associated with the use of LARC and propose a novel study design to address the two main methodological issues that have limited these earlier studies. Namely, we propose to use a randomized controlled trial design and to use a biological marker of semen exposure for measuring changes in condom use.

Teaching condom use skills: practice is superior to observation

Men exposed to a condom skills practice exercise were hypothesized to perform better on condom skills measures than those exposed only to a demonstration or to no intervention. As part of a larger National Institute on Drug Abuse (NIDA) Clinical Trials Network HIV Prevention protocol, men in substance abuse treatment were administered male and female condom use skills measures (MCUS, FCUS) at preintervention, 2 weeks, 3 months, and 6 months postintervention. The MCUS and FCUS scores were compared for 3 intervention exposure groups (demonstration only [DO, n = 149], demonstration plus practice [D+P; n = 112], attended no sessions [NS, n = 139]) across the 4 assessment time points using a mixed effects linear regression model. There is a statistically significant intervention group-by-time effect (P < .0001) for both the MCUS and FCUS. Post hoc, pairwise linear trends across time indicated that for both the MCUS and the FCUS, the D+P group is significantly superior to the DO group and the NS group.

Multilevel social influences on female condom use and adoption among women in the urban United States

Heterosexually transmitted HIV remains of critical concern in the United States and around the world, especially among vulnerable and disadvantaged women, complicated by socioeconomic circumstances, gender power, addiction, and experiences of abuse, among other conditions. Effective woman-initiated HIV prevention options, such as the female condom (FC), are needed that women can use in different sexual relationship contexts. We conducted a behavioral and attitudinal survey with 461 primarily African American and Latina (especially Puerto Rican) women in Hartford, Connecticut, to measure factors on the individual, partner relationship, peer, and community levels influencing their initial and continued use of FC (using the prototype FC1) for disease prevention. We used multivariate analyses and structural equation modeling to assess effects of multiple level factors on FC use and unprotected sex with primary, casual, and paying partners. Initial, recent, and continued FC use was associated with factors on the individual level (education, marital status, drug use, child abuse experiences, HIV status), partner level (number of sex partners, paying sex partner, relationship power), and peer level (more or influential peers saying positive things about FC). Community level factors of availability and support were consistently poor across all sectors, which limited overall FC use. Patterns differed between African American and Latina women in stages and contexts of FC use and unprotected sex. FC can make a valuable contribution to reducing heterosexually transmitted HIV among women in many circumstances. The greatest barrier to increased FC use is the lack of a supportive community environment for its promotion and use.

Biomarker validation of reports of recent sexual activity: results of a randomized controlled study in Zimbabwe

Challenges in the accurate measurement of sexual behavior in human immunodeficiency virus (HIV) prevention research are well documented and have prompted discussion about whether valid assessments are possible. Audio computer-assisted self-interviewing (ACASI) may increase the validity of self-reported behavioral data. In 2006-2007, Zimbabwean women participated in a randomized, cross-sectional study that compared self-reports of recent vaginal sex and condom use collected through ACASI or face-to-face interviewing (FTFI) with a validated objective biomarker of recent semen exposure (prostate-specific antigen (PSA) levels). Of 910 study participants, 196 (21.5%) tested positive for PSA, an indication of semen exposure during the previous 2 days. Of these 196 participants, 23 (11.7%) reported no sex in the previous 2 days, with no difference in reported sexual activity between interview modes (12.5% ACASI vs. 10.9% FTFI; Fisher's exact test: P = 0.72). In addition, 71 PSA-positive participants (36.2%) reported condom-protected vaginal sex only; their reports also indicated no difference between interview modes (33.7% ACASI vs. 39.1% FTFI; P = 0.26). Only 52% of PSA-positive participants reported unprotected sex during the previous 2 days. Self-report was a poor predictor of recent sexual activity and condom use in this study, regardless of interview mode, providing evidence that such data should be interpreted cautiously.

Biomarkers of semen exposure

Biomarkers of semen exposure have historically played their most important role in forensics, i.e., determining whether ejaculation took place in the course of a crime. However, it is becoming increasingly recognized that biomarkers of semen exposure can be useful in the development of new vaginal methods of HIV/sexually transmitted infections (STI) prevention and contraception. This review is based on the presentations of Drs. Michael Coppola (ContraVac, Inc.), Maurizio Macaluso (Centers for Disease Control and Prevention), Andrezej Kulczycki (University of Alabama at Birmingham), Christine Mauck (CONRAD), Robin Maguire (Population Council), and the subsequent discussion led by Drs. Susan Ballagh (CONRAD) and Johan Melendez (Johns Hopkins University) during a session entitled "Biomarkers of semen exposure" held during the conference entitled "Biomarkers for evaluation of vaginal microbicides and contraceptives: Discovery and early validation," organized by CONRAD and the Alliance for Microbicide Development in November of 2006.

Biomedical interventions to prevent HIV infection: evidence, challenges, and way forward

Intensive research efforts for more than two decades have not yet resulted in an HIV vaccine of even moderate effectiveness. However, some progress has been made with other biomedical interventions, albeit on the basis of inconsistent levels of evidence. The male condom, if used correctly and consistently, has been proven in observational studies to be very effective in blocking HIV transmission during sexual intercourse; and, in three randomised trials, male circumcision was protective against HIV acquisition among men. Treatment of sexually transmitted infections, a public health intervention in its own right, has had mixed results, depending in part on the epidemic context in which the approach was assessed. Finally, oral and topical antiretroviral compounds are being assessed for their role in reduction of HIV transmission during sexual intercourse. Research on biomedical interventions poses formidable challenges. Difficulties with product adherence and the possibility of sexual disinhibition are important concerns. Biomedical interventions will need to be part of an integrative package that includes biomedical, behavioural, and structural interventions. Assessment of such multicomponent approaches with moderate effects is difficult. Issues to be considered include the nature of control groups and the effect of adherence on the true effectiveness of the intervention.

Prostate-specific antigen in vaginal fluid after exposure to known amounts of semen and after condom use: comparison of self-collected and nurse-collected samples

BACKGROUND

Prostate-specific antigen (PSA) in vaginal fluid indicates exposure to semen, and was used to assess condom effectiveness, although validity and reliability have not been fully evaluated. Our objective was to compare PSA in self-collected samples with samples collected by a nurse.

METHODS

We conducted two studies, each with 100 women aged 18-48 years. In the first, a nurse exposed each participant to her partner's semen (10, 100 and 1000 microl), and nurse and participant collected samples. In the second, each participant sampled before and after using two male condoms (MC) and two female condoms (FC); a nurse collected another sample afterwards.

RESULTS

PSA concentration increased with semen exposure, but was lower in nurse-collected samples. Both procedures were sensitive, almost 100% after exposure to 100-1000 microl of semen. PSA detection rates with MC and FC were 13% and 28% in self-collected samples, 8% and 9% in nurse-collected samples. Concordance between sample types was 93% with the MC (95% CI: 89%; 96%), 78% with the FC (95% CI: 72%; 84%). PSA decay between sampling times may explain higher values in self-collected samples.

CONCLUSIONS

PSA is a highly sensitive surrogate endpoint for condom effectiveness studies. Self-collected and nurse-collected samples are equivalent, but sample collection timing is critical.

Evaluation of semen detection in vaginal secretions: comparison of four methods

PROBLEM

To determine the best method to detect semen in human vaginal secretions.

METHOD OF STUDY

Vaginal secretions from 302 pregnant women at mean 11.8 weeks' gestation were analyzed. Semen detection was assessed with: (i) measurement of total prostate-specific antigen (PSA), (ii) acid phosphatase activity, (iii) microscopic measurement of spermatozoa on Gram stain, and (iv) self-reported sexual intercourse in the past 2 days. Sensitivity and specificity were calculated for each technique in comparison with PSA levels.

RESULTS

A total of 119 (39.4%) women had a detectable PSA. Compared with measurable PSA, the sensitivity and specificity for other methods were: acid phosphatase (26.9%, 98.4%), Gram stain (36.1%, 98.4%), and self-report of intercourse in the past 48 hr (41.9%, 88.8%).

CONCLUSION

Compared with PSA levels, commonly used assays for recent semen exposure are inaccurate. This inaccuracy may affect the results of studies, which measure vaginal immune factors like cytokines or retrieve DNA from vaginal specimens.

Condom use and vaginal Y-chromosome detection: the specificity of a potential biomarker

OBJECTIVE

Detection of vaginal Y-chromosome sequences (YCS) may be a useful biomarker to validate sexual behavior reporting in women. We describe the effects of condom use on the detection of vaginal YCS.

METHODS

Fifty-six women were asked to abstain from sexual intercourse for 14 days. On day 15, participants were asked to engage in sexual intercourse with their male partners using condoms. Self-collected vaginal swabs were obtained on days 14, 16, and 17. YCS were detected using the Roche LightCycler with the use of positive controls.

RESULTS

Fourty-four of 56 women completed the study. Five women (11.4%) had detectable YCS. The overall specificity of the YCS assay with condom use was 92% (95% CI: 80%-98%). Although women who reported receptive oral sex and digital penetration within 48 hours of swab collection had a higher detection rate of YCS [RR 2.3 (95% CI: 1.1-4.6) and 3.6 (95%CI: 1.6-8.5), respectively], the mean concentration of YCS was much less than that associated with unprotected vaginal intercourse (P <0.001)

CONCLUSIONS

Condom use during intercourse appears to prevent vaginal YCS detection; this may be a useful biomarker to validate self-reported condom use.

Self-reported mechanical problems during condom use and semen exposure. Comparison of two randomized trials in the United States of America and Brazil

OBJECTIVES/GOAL

To compare self-reported condom use problems and objectively determined semen exposure in 2 populations.

STUDY DESIGN

Two randomized crossover trials in the United States and Brazil compared the failure rates of the female condom (FC) and male condom (MC). Participants used both condom types, completed condom-specific questionnaires to report problems, and collected precoital and postcoital samples of vaginal fluid. Prostate-specific antigen (PSA) was detected by immunoassay.

RESULTS

Problems with condom use were reported less frequently in the Brazilian study (rate difference: FC = 24%, P <0.0001, MC = 5%, P = 0.003). By contrast, the PSA detection rates were similar for both the FC and the MC (rate difference: FC = 2%, MC = 1%, not significant). These results suggest that the PSA detection rate was similar in the 2 study groups and that self-reported problems may be a less reliable measure of condom failure.

CONCLUSIONS

Use of biomarkers of condom failure like PSA may help to strengthen the validity of studies promoting behavior change for the prevention of sexually transmitted diseases.

Biomarkers of semen in the vagina: applications in clinical trials of contraception and prevention of sexually transmitted pathogens including HIV

Biomarkers of vaginal exposure to semen, long used in forensic medicine, are now becoming important in the development of vaginal microbicides to prevent HIV/STIs and the development of contraceptives. Semen biomarkers could help evaluate the safety of a new physical or chemical barrier, give preliminary indication of the effectiveness of physical barriers such as diaphragms or condoms, and provide information on unprotected intercourse among participants in a clinical trial who have been advised to use condoms. Candidate biomarkers of semen exposure fall into two broad categories: (1) biomarkers of seminal plasma, among which prostate-specific antigen (PSA) is the best characterized; and (2) biomarkers of spermatozoa and other cells present in semen. This paper, authored by a working group of investigators performing research in the field of semen biomarkers, summarizes the characteristics of an ideal semen biomarker, reviews preclinical and clinical data on existing and potential biomarkers, and outlines the steps that should be carried out to develop an improved biomarker of semen exposure.

Advance provision of emergency contraception for pregnancy prevention (full review)

BACKGROUND

Emergency contraception can prevent pregnancy when taken after unprotected intercourse. Obtaining emergency contraception within the recommended time frame is difficult for many women. Advance provision, in which women receive a supply of emergency contraception before unprotected sex, could circumvent some obstacles to timely use.

OBJECTIVES

To summarize randomized controlled trials evaluating advance provision of emergency contraception to explore effects on pregnancy rates, sexually transmitted infections, and sexual and contraceptive behaviors.

SEARCH STRATEGY

In August 2006, we searched CENTRAL, EMBASE, POPLINE, MEDLINE via PubMed, and a specialized emergency contraception article database. We also searched reference lists and contacted experts to identify additional published or unpublished trials.

SELECTION CRITERIA

We included randomized controlled trials comparing advance provision and standard access, which was defined as any of the following: counseling which may or may not have included information about emergency contraception, or provision of emergency contraception on request at a clinic or pharmacy.

DATA COLLECTION AND ANALYSIS

We evaluated all identified titles and abstracts found for potential inclusion. Two reviewers independently abstracted data and assessed study quality. We entered and analyzed data using RevMan 4.2.8. We calculated odds ratios with 95% confidence intervals for dichotomous data and weighted mean differences with 95% confidence intervals for continuous data.

MAIN RESULTS

Eight randomized controlled trials met our criteria for inclusion, representing 6389 patients in the United States, China and India. Advance provision did not decrease pregnancy rates (OR 1.0; 95% CI: 0.78 to 1.29 in studies for which we included twelve month follow-up data; OR 0.91; 95% CI: 0.69 to 1.19 in studies for which we included six month follow-up data; OR 0.49; 95% CI: 0.09 to 2.74 in a study with three month follow up data), despite increased use (single use: OR 2.52; 95% CI 1.72 to 3.70; multiple use: OR 4.13; 95% CI 1.77 to 9.63) and faster use (weighted mean difference (WMD) -14.6 hours; 95% CI -16.77 to -12.4 hours). Advance provision did not lead to increased rates of sexually transmitted infections (OR 0.99; 95% CI 0.73 to 1.34), increased frequency of unprotected intercourse, nor changes in contraceptive methods. Women who received emergency contraception in advance were equally as likely to use condoms as other women.

AUTHORS' CONCLUSIONS

Advance provision of emergency contraception did not reduce pregnancy rates when compared to conventional provision. Advance provision does not negatively impact sexual and reproductive health behaviors and outcomes. Women should have easy access to emergency contraception, because it can decrease the chance of pregnancy. However, the interventions tested thus far have not reduced overall pregnancy rates in the populations studied.

Long-term female condom use among vulnerable populations in Brazil

We carried out an evaluative study on factors associated with long-term use of female condoms for STI/HIV prevention. A total of 255 women and 29 men who were using female condoms for at least 4 months participated in qualitative/quantitative interviews. The study was conducted in six Brazilian cities. Four primary themes were identified as influencing acceptability and adoption of the female condom: (1) personal "assistance" (counseling) during the early adoption phase; (2) safety; (3) pleasure; and (4) increased sense of power for safer sex negotiation. Alternate use of male and female condoms was the norm among participants, but for approximately one third of the sample, the female condom was the preferred option for safer sex. The study findings suggest that providing clients with explicit and sustained intervention strategies may have a decisive influence on long-term adoption of female condoms.

Performance of the Reality® polyurethane female condom and a synthetic latex prototype: a randomized crossover trial among South African women

OBJECTIVE

This multisite, randomized, crossover trial comparing the performance of the Reality female condom (FC1) with a new synthetic latex prototype (FC2) was conducted in Durban, South Africa.

METHOD

In total, 276 women were enrolled and 201 women completed the study. Altogether, 1910 FC1 condoms and 1,881 FC2 condoms were used.

RESULTS

Total breakage was 0.73% in FC1 and 0.85% in FC2 (95% confidence interval, -0.64 to 0.87). The number of clinical breakages (those that could result in a pregnancy or sexually transmitted infection) was similar for each condom type (FC1, n=9; FC2, n=8). Incorrect penetration (penis between condom and vaginal wall) was 1.26% and 0.64% for FC1 and FC2, respectively. Outer ring displacements (outer ring pushed into the vagina partially or fully) were comparable for both condoms (FC1, 3.14%; FC2, 2.98%). Slippage (condom came out of the vagina) was rare and reported in 0.37% or less of devices used. Total clinical failure was 5.24% in FC1 and 4.3% in FC2.

CONCLUSION

The FC1 and FC2 performed comparably within this trial.