Condom use around the globe: how can we fulfil the prevention potential of male condoms?Lee Warner A C , Maria F. Gallo A and Maurizio Macaluso B
A National Center for Chronic Disease Prevention and Health Promotion, Division of Reproductive Health, Centers for Disease Control and Prevention (CDC), Atlanta, GA 30341 USA.
B Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA.
C Corresponding author. Email: firstname.lastname@example.org
Sexual Health 9(1) 4-9 https://doi.org/10.1071/SH11072
Submitted: 13 May 2011 Accepted: 19 September 2011 Published: 17 February 2012
Despite a global epidemic of sexually transmissible infections and the availability and endorsement of condoms as an effective intervention, the overall use of condoms remains low. This review explores various challenges and opportunities to fully realizing the prevention potential for condoms.
Approximately 340 million incident cases of sexually transmissible infections (STI), including 2.6 million cases of HIV infection,1,2 occur worldwide each year. These infections contribute towards making unsafe sexual intercourse the second leading risk factor for disease, disability or mortality in the poorest countries across the world.3 Given the general absence of available vaccines and microbicides for most STIs (particularly HIV), the use of condoms – a simple technology whose first use for disease prophylaxis (for syphilis) was described by Gabriello Fallopio in 15644,5 – continues to receive attention for its prevention potential. There is general consensus that male condoms must play a central role in any STI/HIV prevention program,6 a stance endorsed by UNAIDS in a recent position statement,7 that deemed the male latex condom ‘... the single most efficient, available technology to reduce the sexual transmission of HIV and other sexually transmitted infections.’ Although there have been marked increases in the public sector distribution8 and use of condoms worldwide in recent years,9 the potential for condoms to significantly influence levels of infection has only been partially realised to date.
When used consistently and correctly, condoms provide protection against a variety of STIs (and also are effective at preventing unintended pregnancy).10 By covering the penile glans and shaft, condoms prevent STIs transmitted primarily to or from the urethra (including gonorrhoea (Neisseria gonorrhoeae), chlamydia (Chlamydia trachomatis), trichomoniasis and HIV) and also STIs transmitted primarily through skin-to-skin contact or contact with mucosal surfaces (including genital herpes, human papillomavirus (HPV), syphilis and chancroid), to the extent that these areas are covered by the condom. In vitro laboratory studies further indicate that latex condoms provide an effective physical barrier to STI pathogens.11–14
Nevertheless, a decade ago, questions surrounding the effectiveness of condoms for STI prevention raised concerns regarding public health recommendations for their promotion and use.15–17 Effectiveness is difficult to quantify because of measurement challenges inherent to clinical studies of condom use, including the absence of randomised controlled trials (and ethical issues precluding inclusion of a non-condom arm to persons at risk), reliance on self-reported measures of condom use, inadequate measures of consistent and correct use, and potentially low study power from infrequent STI outcomes. Because of these limitations, clinical and epidemiologic studies generally tend to underestimate condom effectiveness.18–25 Nevertheless, a growing body of research from clinical studies, spurred by the release of a 2001 US Dept of Health and Human Services report,26 has documented that properly used condoms reduce the risk of many STIs. The strongest evidence comes from cohort studies of heterosexual couples discordant for HIV infection (i.e. one partner is infected and the other is not), where consistent condom use reduces HIV risk by ~80%.27 Additional reviews18,19,28–30 and clinical studies31–35 that have employed improved designs, measurements and analytic methodologies offer further evidence of the protection provided by regular condom use against other STIs, including gonorrhoea, chlamydia, genital herpes, syphilis and HPV. The continued use of improved study designs and condom use measures in future studies will undoubtedly lead over time to more precise estimates of the effectiveness of condoms against individual STIs.
Moving beyond effectiveness
Sufficient evidence now exists to redirect a substantial portion of public health efforts towards better measuring and addressing barriers to consistent and correct use.36 Future studies, for example, could use biological markers of semen exposure detected in vaginal specimens after coitus37 to confirm the specific steps in condom use (e.g. failure to use the condom for the entire act or to withdraw immediately after ejaculation) that are most likely to increase risk of infection transmission.38 Knowledge of the steps that need to be emphasised could improve counselling on the mechanics of condom use, as demonstrated in a recent intervention trial of men diagnosed with STI.39 STI prevention strategies that include a condom component should reinforce and clearly communicate information about effectiveness to potential users, acknowledging that although condoms may not fully eliminate STI risk, their use certainly confers more protection for sexually active persons compared with non-use, and that proficient (consistent and correct) use further reduces the risk of transmission as compared with inconsistent or incorrect use. More accurate research on condom effectiveness is likely to result in improved educational messages and improved condom use and protection. The public perception of condom effectiveness and trust in condom use as a strategy for personal protection are also likely to improve, facilitating the cultural shift that is necessary to establish condom use as a normative behaviour.
Barriers to use
The challenges to fully realising the prevention potential for condoms to address the global STI and HIV epidemics extend far beyond measuring condom effectiveness, however. To better facilitate and promote use of condoms, public health officials should be realistic about both the advantages and drawbacks inherent to condom use. Almost 25 years ago, in one of the first memorable attempts of the U.S. Centers for Disease Control and Prevention (CDC) to place condom advertisements on network television as part of the America Responds to AIDS public information campaign,40,41 one public service announcement showed a man putting on a sock, with the accompanying tagline, ‘Putting on a condom is just as simple’. Although prevention efforts have since progressed considerably, one question the public health community must honestly reflect upon is the extent to which it may oversimplify and downplay the difficulties associated with condoms to prospective users.
Were consistent and correct use simple to achieve, we would expect rates of condom use to be high (and problems with condom use low) across different settings and populations worldwide. Despite promising news suggesting condom use has increased substantially in recent years and remains highest among persons at greatest risk, current levels of use are likely insufficient for preventing the spread of STIs and considerable opportunity for improvement remains. Data from CDC’s national Youth Risk Behaviour Surveys (YRBS), for example, indicate condom use at last intercourse by sexually active high school students in the USA increased markedly since the 1990s, but is still only around 60%;42 comparable figures from the National Survey of Sexual Health and Behaviour estimate 80% use at last intercourse among USA adolescents.43 Condom use is markedly lower among sexually active USA adults, where ~20% overall44,45 – and less than 50% of adults with multiple partners44 – report use at last intercourse. Similarly discouraging patterns of condom use have been reported from general population surveys in other countries for both adolescents46 and adults.47 Likewise, Demographic Health Surveys (DHS) conducted in five sub-Saharan countries, where the HIV burden is high, suggest that condom use at last intercourse increased dramatically among men having higher-risk sex yet still remains only 40–70%.48 There is increasing recognition that sustained condom use requires a level of commitment that may be difficult even for people who know that they are at risk for STIs because of the actual or perceived disadvantages of condom use. Thus, sustained condom use beyond the most recent act of intercourse (e.g. 3–6 months or 1 year) would probably be even lower. Even among studies of heterosexual couples discordant for HIV27 – the same studies that demonstrated the effectiveness of consistent use – fewer than half of participants reported regular use of condoms despite having a known risk for infection and presumably a high motivation to use condoms. Less than optimal rates of male condom use also have been reported from several recent international HIV prevention trials of microbicides and diaphragms, in which participants at increased risk for HIV exposure received intensive condom counselling and an adequate supply of condoms.49–54
Similarly, even when condoms are used, problems can occur. These problems range from those that could directly compromise effectiveness within a particular act of intercourse (e.g. breakage, slippage and failure to use condoms throughout intercourse)18,20,24,55 to those that can directly impact the likelihood of condom use during future acts of intercourse (e.g. loss of erection, loss of sensation or inability to ejaculate).55–58 Two intentional user practices that have received increased attention of late – putting condoms on after starting intercourse or removing condoms before ejaculation20,55,59–63 – illustrate well the challenges of achieving effective use. And although the rate of any of single condom problem generally is low (less than 5–10% of coital acts),55,59 the fraction of users reporting one or more problems often exceeds 40–50% even over brief periods of time.55,62 These examples underscore the reality that condom use, despite features that give an appearance of simplicity (e.g. low technology, low cost and available without prescription), is a multi-faceted task. Even under the best of circumstances, factors such as inexperience,64–67 prior negative experiences with condoms,56,59 or gender or social inequalities in relationships9 make the task inherently more complex and difficult to carry out.
The ability of public health to achieve the full prevention potential for condoms depends on how successfully we acknowledge and address the difficulties associated with using condoms with innovative and practical solutions. In 2004, UNAIDS proposed a four-pronged strategy for maximising the prevention potential of condoms that included: (1) realising there are interactions between condom promotion – including condom social marketing and peer-based condom education – and other prevention strategies; (2) understanding and correctly communicating information on condom effectiveness; 3) convincing people to use condoms when they are needed, and to do so consistently and correctly; and (4) ensuring a sufficient and regular supply of condoms for those who require them.9
Specific areas that have yielded promising results towards increasing use include developing better condoms to increase acceptability and uptake among current and prospective users, as well as improving the accessibility and marketing of condoms in settings worldwide. From a device standpoint, condoms can be improved to make them more acceptable to prospective users. Possible improvements to condoms could include making them easier to apply, less likely to slip off or break, capable of providing the same (or greater) level of sensitivity as unprotected intercourse, and better fitting and more comfortable for men regardless of their penis size.56,68 Such design innovations in condoms are being made in an effort to make use more acceptable to broad populations of prospective users for STI prevention.69–72 Though still representing a very small fraction (~0.2%) of the worldwide condom market,73 condoms designed to be worn by women serve a specific need for female-controlled barriers, and are increasing in popularity and availability.72
From a marketing standpoint, traditional condom marketing that focusses on the value of condoms in preventing STI (or unintended pregnancy) may need to be replaced by or supplemented with marketing that emphasises that sexual satisfaction is possible with the use of condoms for both men and women. Though, ideally, condom use would be the norm for the general population, condom use remains substantially higher in casual relationships.44,74 The promotion of consistent use of condoms within regular partnerships remains a major public health challenge: in some settings, for example, most new cases of HIV among women result from infection transmitted via their husband.75 However, the use of condoms – or suggestion of their use – within a primary relationship may be interpreted as a lack of trust or fidelity,76 or as incompatible with developing or maintaining an intimate, emotional relationship.77,78 Emphasising the positive outcomes from practicing condom-protected intercourse could facilitate their use.79–81
Additionally, simply increasing the availability of or accessibility to condoms has been shown to be efficacious in increasing condom use behaviours.82 Effective aspects of innovative population-level condom social marketing strategies to increase the awareness of the benefits of condom use and to normalise their use (from countries such as India, Kenya83 and Brazil84) should be examined as potential models for widespread use. There also is encouraging evidence that condoms can be successfully incorporated into comprehensive STI prevention strategies that involve multiple prevention messages, as demonstrated by recent examples from Uganda,85 Thailand9 and China.86
Although the emphasis continues to be placed on developing biomedical interventions (e.g. vaccines, microbicides, circumcision), the male latex condom remains the most effective, most widely available and by far the least expensive prevention method. Increasing its use continues to be an important public health priority for comprehensive STI and HIV prevention efforts, which should focus on improving condom devices, increasing their access, and addressing the needs of specific subpopulations and social norms regarding condom use. Finally, addressing the global HIV/STI pandemic will require explicit acknowledgement of the challenges of using condoms. Doing so is essential to fully realising the potential for condom use as a prevention tool.
Conflicts of interest
The findings and conclusions in this article are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. The material in this manuscript was presented in part at the 17th Conference on Retroviruses and Opportunistic Infections (CROI), San Francisco, CA, USA; February 16–19, 2010.
References UNAIDS. Global report: UNAIDS report on the global AIDS epidemic 2010. Geneva: Joint United Nations Programme on HIV/AIDS; 2010. Available online at: www.unaids.org/documents/20101123_GlobalReport_em.pdf [verified March 2011].
 Gerbase AC, Rowley JT, Heymann DH, Berkley SF, Piot P. Global prevalence and incidence estimates of selected curable STDs. Sex Transm Infect 1998; 74 S12–6.
 Ezzati M, Lopez AD, Rodgers A, Vander Hoorn S. Murray CJL and the Comparative Risk Assessment Collaborating Group*. Selected major risk factors and global and regional burden of disease. Lancet 2002; 360 1347–60.
| Murray CJL and the Comparative Risk Assessment Collaborating Group*. Selected major risk factors and global and regional burden of disease.CrossRef |
 Collier A. The humble little condom: a history. Amherst, NY: Prometheus Books; 2007.
 Allen P. Condom: one small item, one giant impact. Oxford: New Internationalist Ltd.; 2007.
 Halperin DT, Steiner MJ, Cassell MM, Green EC, Hearst N, Kirby D, et al The time has come for common ground on preventing sexual transmission of HIV. Lancet 2004; 364 1913–5.
| The time has come for common ground on preventing sexual transmission of HIV.CrossRef |
 UNAIDS. Condoms and HIV prevention: position statement by UNAIDS, UNFPA and WHO. Geneva: UNAIDS; 2009. Available online at: www.unaids.org/en/resources/presscentre/featurestories/2009/march/20090319preventionposition/ [verified March 2011].
 United Nations Population Fund (UNFPA). Donor support for contraceptives and condoms for STI/HIV prevention. New York: UNFPA; 2008.
 UNAIDS. Making condoms work for HIV prevention: cutting-edge perspectives. Geneva: UNAIDS; 2004.
 Workowski KA, Berman SM, Centers for Disease Control and Prevention (CDC) Sexually transmitted diseases treatment guidelines. MMWR Morb Mortal Wkly Rep 2010; 59 1–110.
 Carey RF, Lytle CD, Cyr WH. Implications of laboratory tests of condom integrity. Sex Transm Dis 1999; 26 216–20.
| Implications of laboratory tests of condom integrity.CrossRef | 1:STN:280:DyaK1M3ktVWiuw%3D%3D&md5=008c5205cd6afbc838cc06e983674ce9CAS |
 Carey RF, Herman WA, Retta SM, Rinaldi JE, Herman BA, Athey TW. Effectiveness of latex condoms as a barrier to human immunodeficiency virus-sized particles under conditions of simulated use. Sex Transm Dis 1992; 19 230–4.
| Effectiveness of latex condoms as a barrier to human immunodeficiency virus-sized particles under conditions of simulated use.CrossRef | 1:STN:280:DyaK3s%2FjtFWiuw%3D%3D&md5=275d6ffa269512559095650f5992cb2aCAS |
 Van de Perre P, Jacobs D, Sprecher-Goldberger S. The latex condom, an efficient barrier against sexual transmission of AIDS-related viruses. AIDS 1987; 1 49–52.
| 1:STN:280:DyaL1c7gslSntA%3D%3D&md5=5cfb0bb2728860c70004de98b346e0ccCAS |
 Rietmeijer CA, Krebs JW, Feorino PM, Judson FN. Condoms as physical and chemical barriers against human immunodeficiency virus. JAMA 1988; 259 1851–3.
| Condoms as physical and chemical barriers against human immunodeficiency virus.CrossRef | 1:STN:280:DyaL1c7ktFGmsA%3D%3D&md5=bd58441d212c13393245cccd6c4f848bCAS |
 Cates W. The NIH condom report: the glass is 90% full. Fam Plann Perspect 2001; 33 231–3.
| The NIH condom report: the glass is 90% full.CrossRef |
 Boonstra H. Public health advocates say campaign to disparage condoms threatens STD prevention efforts. Guttmacher Rep Public Policy 2003; 6 1–3.
 Gilden D. Condom effectiveness, reviewed, revised, reduxed. New York: Community HIV/AIDS Mobilization Project (CHAMP) HHS Watch; 2005. Available online at: http://www.champnetwork.org/media/HHSWatch0705.pdf [verified March 2011].
 Warner L, Stone KM, Macaluso M, Buehler JW, Austin HD. Condom use and risk of gonorrhea and chlamydia: a systematic review of design and measurement factors assessed in epidemiologic studies. Sex Transm Dis 2006; 33 36–51.
| Condom use and risk of gonorrhea and chlamydia: a systematic review of design and measurement factors assessed in epidemiologic studies.CrossRef |
 Crosby RA, Bounse S. Condom effectiveness: where are we now? Sex Health 2012; 9 10–17.
 Crosby R, DiClemente RJ, Holtgrave DR, Wingood GM. Design, measurement, and analytical considerations for testing hypotheses relative to condom effectiveness against non-viral STIs. Sex Transm Infect 2002; 78 228–31.
| Design, measurement, and analytical considerations for testing hypotheses relative to condom effectiveness against non-viral STIs.CrossRef | 1:STN:280:DC%2BD38vjvFehtQ%3D%3D&md5=309ffc63b433761a654aee6878d11949CAS |
 Steiner MJ, Feldblum PJ, Padian N. Invited commentary: condom effectiveness – will prostate-specific antigen shed new light on this perplexing problem? Am J Epidemiol 2003; 157 298–300.
| Invited commentary: condom effectiveness – will prostate-specific antigen shed new light on this perplexing problem?CrossRef |
 Taylor D. Issues in the design, analysis and interpretation of condom functionality studies. Contraception 2009; 80 237–44.
| Issues in the design, analysis and interpretation of condom functionality studies.CrossRef |
 Noar SM, Cole C, Carlyle K. Condom use measurement in 56 studies of sexual risk behavior: review and recommendations. Arch Sex Behav 2006; 35 327–45.
| Condom use measurement in 56 studies of sexual risk behavior: review and recommendations.CrossRef |
 Sanders SA, Yarber WL, Kaufman EL, Crosby RA, Graham CA, Milhausen RR. Condom use errors and problems: a global view. Sex Health 2012; 9 81–95.
 Lagakos SW, Gable AR (editors). Methodological challenges in biomedical HIV prevention trials. Washington DC: National Academies Press; 2008.
 National Institute of Allergy and Infectious Diseases (NIAID). Workshop summary: scientific evidence on condom effectiveness for sexually transmitted disease (STD) prevention. Bethesda, MD: NIAID; 2001.
 Weller S, Davis K. Condom effectiveness in reducing heterosexual HIV transmission. Cochrane Database Syst Rev 2002; CD003255
| 1:STN:280:DC%2BD383ksl2msw%3D%3D&md5=f17e26fc8b90a47e28618fb1e64e60ebCAS |
 Holmes KK, Levine R, Weaver M. Effectiveness of condoms in preventing sexually transmitted infections. Bull World Health Organ 2004; 82 454–61.
 Koss CA, Dunne EF, Warner L. A systematic review of epidemiologic studies assessing condom use and risk of syphilis. Sex Transm Dis 2009; 36 401–5.
| A systematic review of epidemiologic studies assessing condom use and risk of syphilis.CrossRef |
 Martin ET, Krantz E, Gottlieb SL, Magaret AS, Langenberg A, Stanberry L, et al A pooled analysis of the effect of condoms in preventing HSV-2 acquisition. Arch Intern Med 2009; 169 1233–40.
| A pooled analysis of the effect of condoms in preventing HSV-2 acquisition.CrossRef |
 Wald A, Langenberg AG, Krantz E, Douglas JM, Handsfield HH, DiCarlo RP, et al The relationship between condom use and herpes simplex virus acquisition. Ann Intern Med 2005; 143 707–13.
 Winer RL, Hughes JP, Feng Q, O’Reilly S, Kiviat NB, Holmes KK, et al Condom use and the risk of genital human papillomavirus infection in young women. N Engl J Med 2006; 354 2645–54.
| Condom use and the risk of genital human papillomavirus infection in young women.CrossRef | 1:CAS:528:DC%2BD28XmtFSgtLo%3D&md5=29d6e35802dc767bbad2a5dc568b0cd1CAS |
 Warner L, Newman D, Peterman T, Kamb M, Douglas JM, Zenilman J, et al Condom effectiveness for reducing transmission of gonorrhea and chlamydia: the importance of assessing partner infection status. Am J Epidemiol 2004; 159 242–51.
| Condom effectiveness for reducing transmission of gonorrhea and chlamydia: the importance of assessing partner infection status.CrossRef |
 Warner L, Macaluso M, Austin HD, Kleinbaum DK, Artz L, Fleenor ME, et al Application of the case-crossover design to reduce unmeasured confounding in studies of condom effectiveness. Am J Epidemiol 2005; 161 765–73.
| Application of the case-crossover design to reduce unmeasured confounding in studies of condom effectiveness.CrossRef |
 Macaluso M, Blackwell R, Jamieson DJ, Kulczycki A, Chen MP, Akers R, et al Efficacy of the male latex condom and of the female polyurethane condom as barriers to semen during intercourse: a randomized clinical trial. Am J Epidemiol 2007; 166 88–96.
| Efficacy of the male latex condom and of the female polyurethane condom as barriers to semen during intercourse: a randomized clinical trial.CrossRef |
 Crosby R, Warner L. Pending research issues in male condom use promotion. Sex Health 2008; 5 317–9.
| Pending research issues in male condom use promotion.CrossRef |
 Mauck CK, Doncel GF. Biomarkers of semen in the vagina: applications in clinical trials of contraception and prevention of sexually transmitted pathogens including HIV. Contraception 2007; 75 407–19.
| Biomarkers of semen in the vagina: applications in clinical trials of contraception and prevention of sexually transmitted pathogens including HIV.CrossRef | 1:CAS:528:DC%2BD2sXls1aisrc%3D&md5=f491f804d2232c713529ff1212285fcbCAS |
 Duerr A, Gallo MF, Warner L, Jamieson DJ, Kulczycki A, Macaluso M. Measures of male condom failure and incorrect use. Sex Transm Dis 2011;
 Crosby R, DiClemente RJ, Charnigo R, Snow G, Troutman A. A brief, clinic-based, safer sex intervention for heterosexual African American men newly diagnosed with an STD: a randomized controlled trial. Am J Public Health 2009; 99 S96–103.
| A brief, clinic-based, safer sex intervention for heterosexual African American men newly diagnosed with an STD: a randomized controlled trial.CrossRef |
 Keiser NH. Strategies of media marketing for “America Responds to AIDS” and applying lessons learned. Public Health Rep 1991; 106 623–7.
| 1:STN:280:DyaK38%2Fms1OjsQ%3D%3D&md5=9e93869b4b593f80a3a71c44f39ced8dCAS |
 Centers for Disease Control and Prevention (CDC) Evolution of HIV/AIDS prevention programs – United States, 1981–2006. MMWR Morb Mortal Wkly Rep 2006; 55 597–603.
 Pazol K, Warner L, Gavin L, Callaghan WM, Spitz AM, Anderson JE, et al Teen pregnancy – United States, 1991–2009. MMWR Morb Mortal Wkly Rep 2011; 60 414–20.
 Fortenberry JD, Schick V, Herbenick D, Sanders SA, Dodge B, Reece M. Sexual behaviors and condom use at last vaginal intercourse: a national sample of adolescents ages 14 to 17 years. J Sex Med 2010; 7 305–14.
| Sexual behaviors and condom use at last vaginal intercourse: a national sample of adolescents ages 14 to 17 years.CrossRef |
 Anderson J, Warner L, Macaluso M. Condom use among U.S. adults at last sexual intercourse, 1996–2008: an update from national survey data. Sex Transm Dis 2011; 38 919–21.
 Sanders SA, Reece M, Herbenick D, Schick V, Dodge B, Fortenberry JD. Condom use during most recent vaginal intercourse event among a probability sample of adults in the United States. J Sex Med 2010; 7 362–73.
| Condom use during most recent vaginal intercourse event among a probability sample of adults in the United States.CrossRef |
 Godeau E, Gabhainn SN, Vignes C, Ross J, Boyce W, Todd J. Contraceptive use by 15-year-old students at their last sexual intercourse: results from 24 countries. Arch Pediatr Adolesc Med 2008; 162 66–73.
| Contraceptive use by 15-year-old students at their last sexual intercourse: results from 24 countries.CrossRef |
 Johnson AM, Mercer CH, Erens B, Copas AJ, McManus S, Wellings K, et al Sexual behaviour in Britain: partnership, practices, and HIV risk behaviours. Lancet 2001; 358 1835–42.
| Sexual behaviour in Britain: partnership, practices, and HIV risk behaviours.CrossRef | 1:STN:280:DC%2BD3MjgtVCmtw%3D%3D&md5=67fb9695b7634672e4bbfc7e25710742CAS |
 Adair T. Men’s condom use in higher-risk sex: trends and determinants in five sub-Saharan countries. DHS Working Paper 2008; 34: 1–29.
 Padian NS, van der Straten A, Ramjee G, Chipato T, de Bruyn G, Blanchard K, et al Diaphragm and lubricant gel for prevention of HIV acquisition in southern African women: a randomised controlled trial. Lancet 2007; 370 251–61.
| Diaphragm and lubricant gel for prevention of HIV acquisition in southern African women: a randomised controlled trial.CrossRef |
 Skoler-Karpoff S, Ramjee G, Ahmed K, Altini L, Plagianos MG, Friedland B, et al Efficacy of Carraguard for prevention of HIV infection in women in South Africa: a randomised, double-blind, placebo-controlled trial. Lancet 2008; 372 1977–87.
| Efficacy of Carraguard for prevention of HIV infection in women in South Africa: a randomised, double-blind, placebo-controlled trial.CrossRef | 1:CAS:528:DC%2BD1cXhsVKlsLvN&md5=72e45aa11111c0ef639531dfad118311CAS |
 Van Damme L, Govinden R, Mirembe FM, Guédou F, Solomon S, Becker ML, et al Lack of effectiveness of cellulose sulfate gel for the prevention of vaginal HIV transmission. N Engl J Med 2008; 359 463–72.
| Lack of effectiveness of cellulose sulfate gel for the prevention of vaginal HIV transmission.CrossRef | 1:CAS:528:DC%2BD1cXpt1Shu7c%3D&md5=be96630e8368ad33bb5491f57a86d963CAS |
 McCormack S, Ramjee G, Kamali A, Rees H, Crook AM, Gafos M, et al PRO2000 vaginal gel for prevention of HIV-1 infection (Microbicides Development Programme 301): a phase 3, randomised, double-blind, parallel-group trial. Lancet 2010; 376 1329–37.
| PRO2000 vaginal gel for prevention of HIV-1 infection (Microbicides Development Programme 301): a phase 3, randomised, double-blind, parallel-group trial.CrossRef | 1:CAS:528:DC%2BC3cXht12ks7nN&md5=1cf270eb1d7aab95e9b5ab91cb8d1cbbCAS |
 Abdool Karim Q, Abdool Karim SS, Frohlich JA, Grobler AC, Baxter C, Mansoor LE, et al Effectiveness and safety of tenofovir gel, an antiretroviral microbicide, for the prevention of HIV infection in women. Science 2010; 329 1168–74.
| Effectiveness and safety of tenofovir gel, an antiretroviral microbicide, for the prevention of HIV infection in women.CrossRef | 1:CAS:528:DC%2BC3cXhtV2hsr%2FI&md5=8285ce242cb3cffcd596b459dfca99e7CAS |
 Abdool Karim SS, Richardson BA, Ramjee G, Hoffman IF, Chirenje ZM, Taha T, et al Safety and effectiveness of BufferGel and 0.5% PRO2000 gel for the prevention of HIV infection in women. AIDS 2011; [Epub ahead of print.]
| Safety and effectiveness of BufferGel and 0.5% PRO2000 gel for the prevention of HIV infection in women.CrossRef |
 Warner L, Newman DR, Kamb ML, Fishbein M, Douglas JM, Zenilman J, et al Problems with condom use among patients attending sexually transmitted disease clinics: prevalence, predictors, and relation to incident gonorrhea and chlamydia. Am J Epidemiol 2008; 167 341–9.
| Problems with condom use among patients attending sexually transmitted disease clinics: prevalence, predictors, and relation to incident gonorrhea and chlamydia.CrossRef |
 Crosby RA, Yarber WL, Graham CA, Sanders SA. Does it fit okay? Problems with condom use as a function of self-reported poor fit. Sex Transm Infect 2010; 86 36–8.
| Does it fit okay? Problems with condom use as a function of self-reported poor fit.CrossRef | 1:STN:280:DC%2BC3c7gvVymtg%3D%3D&md5=cf3096a45e3f87c84e4f1e36d7b02156CAS |
 Khan SI, Hudson-Rodd N, Saggers S, Bhuiyan MI, Bhuiya A. Safer sex or pleasurable sex? Rethinking condom use in the AIDS era. Sex Health 2004; 1 217–25.
| Safer sex or pleasurable sex? Rethinking condom use in the AIDS era.CrossRef |
 Graham CA, Crosby R, Yarber WL, Sanders SA, McBride K, Milhausen RR, et al Erection loss in association with condom use among young men attending a public STI clinic: potential correlates and implications for risk behaviour. Sex Health 2006; 3 255–60.
| Erection loss in association with condom use among young men attending a public STI clinic: potential correlates and implications for risk behaviour.CrossRef |
 Warner L, Clay-Warner J, Boles J, Williamson J. Assessing condom use practices. Implications for evaluating method and user effectiveness. Sex Transm Dis 1998; 25 273–7.
| Assessing condom use practices. Implications for evaluating method and user effectiveness.CrossRef | 1:STN:280:DyaK1czislalsw%3D%3D&md5=903ea8278fd7489092047079f1e30d71CAS |
 Paz-Bailey G, Koumans EH, Sternberg M, Pierce A, Papp J, Unger ER, et al The effect of correct and consistent condom use on chlamydial and gonococcal infection among urban adolescents. Arch Pediatr Adolesc Med 2005; 159 536–42.
| The effect of correct and consistent condom use on chlamydial and gonococcal infection among urban adolescents.CrossRef |
 Calzavara L, Burchell AN, Remis RS, Major C, Corey P, Myers T, et al Delayed application of condoms is a risk factor for human immunodeficiency virus infection among homosexual and bisexual men. Am J Epidemiol 2003; 157 210–7.
| Delayed application of condoms is a risk factor for human immunodeficiency virus infection among homosexual and bisexual men.CrossRef |
 Hatherall B, Ingham R, Stone N, McEachran J. How, not just if, condoms are used: the timing of condom application and removal during vaginal sex among young people in England. Sex Transm Infect 2007; 83 68–70.
| How, not just if, condoms are used: the timing of condom application and removal during vaginal sex among young people in England.CrossRef | 1:STN:280:DC%2BD2s%2FnvVeqsA%3D%3D&md5=376772be73946cdf171ad3270c78e127CAS |
 Hensel DJ, Stupiansky NW, Herbenick D, Dodge B, Reece M. When condom use is not condom use: an event-level analysis of condom use behaviors during vaginal intercourse. J Sex Med 2011; 8 28–34.
| When condom use is not condom use: an event-level analysis of condom use behaviors during vaginal intercourse.CrossRef |
 Albert AE, Warner DL, Hatcher RA, Trussell J, Bennett C. Condom use among female commercial sex workers in Nevada’s legal brothels. Am J Public Health 1995; 85 1514–20.
| Condom use among female commercial sex workers in Nevada’s legal brothels.CrossRef | 1:STN:280:DyaK28%2Fjs1Grsg%3D%3D&md5=bff775537cb41f1ccc03bfbc65a55134CAS |
 Macaluso M, Kelaghan J, Artz L, Austin H, Fleenor M, Hook EW, et al Mechanical failure of the latex condom in a cohort of women at high STD risk. Sex Transm Dis 1999; 26 450–8.
| Mechanical failure of the latex condom in a cohort of women at high STD risk.CrossRef | 1:STN:280:DyaK1MvitlWhtQ%3D%3D&md5=a4c74bc1a117ed2318dfb24b98093ad2CAS |
 Spruyt A, Steiner MJ, Joanis C, Glover LH, Piedrahita C, Alvarado G, et al Identifying condom users at risk for breakage and slippage: findings from three international sites. Am J Public Health 1998; 88 239–44.
| Identifying condom users at risk for breakage and slippage: findings from three international sites.CrossRef | 1:STN:280:DyaK1c7ltFOitg%3D%3D&md5=cacf2c979696cb07fc94673475d47d36CAS |
 Steiner M, Piedrahita C, Glover L, Joanis C. Can condom users likely to experience condom failure be identified? Fam Plann Perspect 1993; 25 220–3, 226.
| Can condom users likely to experience condom failure be identified?CrossRef | 1:STN:280:DyaK2c%2FosFGgtA%3D%3D&md5=55ba74202ac334f554116987df4e2373CAS |
 Cecil M, Nelson A, Trussell J, Hatcher R. If the condom doesn’t fit, you must resize it. Contraception 2010; 82 489–90.
| If the condom doesn’t fit, you must resize it.CrossRef |
 Trussell J, Warner DL, Hatcher RA. Condom slippage and breakage rates. Fam Plann Perspect 1992; 24 20–3.
| Condom slippage and breakage rates.CrossRef | 1:STN:280:DyaK383ovF2rug%3D%3D&md5=6d2876be2cff124787f359d62f1fd3afCAS |
 Cook L, Nanda K, Taylor D. Randomized crossover trial comparing the eZ. on plastic condom and a latex condom. Contraception 2001; 63 25–31.
| Randomized crossover trial comparing the eZ. on plastic condom and a latex condom.CrossRef | 1:STN:280:DC%2BD3M3ntVaitQ%3D%3D&md5=9e7c7d835758323c2a3606f4f3a475c9CAS |
 Gallo MF, Grimes DA, Lopez LM, Schulz KF. Non-latex versus latex male condoms for contraception. Cochrane Database Syst Rev 2006; 1 CD003550
 Gallo M, Kilbourne-Brook M, Coffey PS. A review of the effectiveness and acceptability of the female condom for dual protection. Sex Health 2011; 9 18–26.
 Anonymous. Condoms: a global strategic business report. San Jose: Global Industry Analysts Inc.; 2008.
 Macaluso M, Demand MJ, Artz LM, Hook EW. Partner type and condom use. AIDS 2000; 14 537–46.
| Partner type and condom use.CrossRef | 1:STN:280:DC%2BD3c3ktFKhug%3D%3D&md5=35a03628a3d5714892d6841b6496a5e0CAS |
 United Nations Population Fund (UNPFA). State of world population 2005. The promise of equality, gender equity, reproductive health and the millennium development goals. New York: UNPF; 2005.
 Marston C, King E. Factors that shape young people’s sexual behaviour: a systematic review. Lancet 2006; 368 1581–6.
| Factors that shape young people’s sexual behaviour: a systematic review.CrossRef |
 Corbett AM, Dickson-Gómez J, Hilario H, Weeks MR. A little thing called love: condom use in high-risk primary heterosexual relationships. Perspect Sex Reprod Health 2009; 41 218–24.
| A little thing called love: condom use in high-risk primary heterosexual relationships.CrossRef |
 Thomsen S, Stalker M, Toroitich-Ruto C. Fifty ways to leave your rubber: how men in Mombasa rationalise unsafe sex. Sex Transm Infect 2004; 80 430–4.
| Fifty ways to leave your rubber: how men in Mombasa rationalise unsafe sex.CrossRef | 1:STN:280:DC%2BD2crpvFGltA%3D%3D&md5=3b530affb682419b0857ff4a03251cbeCAS |
 Higgins JA, Hoffman S, Graham CA, Sanders SA. Relationships between condoms, hormonal methods, and sexual pleasure and satisfaction: an exploratory analysis from the Women’s Well-Being and Sexuality Study. Sex Health 2008; 5 321–30.
| Relationships between condoms, hormonal methods, and sexual pleasure and satisfaction: an exploratory analysis from the Women’s Well-Being and Sexuality Study.CrossRef |
 Philpott A, Knerr W, Maher D. Promoting protection and pleasure: amplifying the effectiveness of barriers against sexually transmitted infections and pregnancy. Lancet 2006; 368 2028–31.
| Promoting protection and pleasure: amplifying the effectiveness of barriers against sexually transmitted infections and pregnancy.CrossRef |
 Randolph ME, Pinkerton SD, Bogart LM, Cecil H, Abramson PR. Sexual pleasure and condom use. Arch Sex Behav 2007; 36 844–8.
| Sexual pleasure and condom use.CrossRef |
 Charania MR, Crepaz N, Guenther-Gray G, Henny K, Liau A, Willis LA, et al Efficacy of structural-level condom distribution interventions: a meta-analysis of U.S. and international studies, 1998. AIDS Behav 2011; 15 1283–97.
 UNAIDS. Condom social marketing: selected case studies. Geneva: UNAIDS; 2000.
 Okie S. Fighting HIV – lessons from Brazil. N Engl J Med 2006; 354 1977–81.
| Fighting HIV – lessons from Brazil.CrossRef | 1:CAS:528:DC%2BD28XksFGhs74%3D&md5=72c71d454deb870c9104ab07e73358d2CAS |
 Singh S, Darroch JE, Bankole A. A, B and C in Uganda: the roles of abstinence, monogamy and condom use in HIV decline. Reprod Health Matters 2004; 12 129–35.
| A, B and C in Uganda: the roles of abstinence, monogamy and condom use in HIV decline.CrossRef |
 Sun X, Lu F, Wu Z, Poundstone K, Zeng G, Xu P, et al Evolution of information-driven HIV/AIDS policies in China. Int J Epidemiol 2010; 39 ii4–13.
| Evolution of information-driven HIV/AIDS policies in China.CrossRef |