Men who have sex with men (MSM) aremen who engage insexual activity with other men, regardless of theirsexual orientation orsexual identity.[1][2] The term was created byepidemiologists in the 1990s, to better study and communicate the spread ofsexually transmitted infections such asHIV/AIDS between all sexually active males, not strictly those identifying asgay,bisexual,pansexual or various other sexualities,[1] but also for examplemale prostitutes. The term is often used in medical literature andsocial research to describe such men as a group. It does not describe any specific kind of sexual activity, and which activities are covered by the term depends on context. The alternative term "males who have sex with males" is sometimes considered more accurate in cases where those described may not belegal adults.[2]
As a constructed category
The termmen who have sex with men had been in use inpublic health discussions, especially in the context ofHIV/AIDS, since 1990 or earlier, but the coining of theinitialism byGlicket al. in 1994 "signaled the crystallization of a new concept."[3][4] This behavioral concept comes from two distinct academic perspectives. First, it was pursued byepidemiologists seeking behavioral categories that would offer better analytical concepts for the study of disease-risk than identity-based categories (such as "gay", "bisexual", or "straight"), because a man who self-identifies as straight may nonetheless be sexually active with other men; similarly, a man who self-identifies as gay or bisexual is not necessarily sexually active with other men. Second, the concept's usage is tied to criticism ofsexual identity terms prevalent insocial construction literature, which typically rejected the use of identity-based concepts across cultural and historical contexts.The Huffington Post postulates that the termMSM was created byCleo Manago, who is also credited for coining the term "same gender loving" (SGL).[5]
MSM are not limited to small, self-identified, and visible sub-populations.MSM andgay refer to different things: behaviors and social identities.MSM refers to sexual activities between men, regardless of how they identify, whereasgay can include those activities but is more broadly seen as a cultural identity.Homosexuality refers to sexual/romantic attraction between members of the same sex and may or may not include romantic relationships.Gay is a social identity and is generally the preferred social term, whereashomosexual is used in formal contexts, though the terms are not entirely interchangeable. Men who arenon-heterosexual orquestioning may identify with all, none, a combination of these, or one of the newer terms indicating a similar sexual, romantic, and cultural identity likebi-curious.
In their assessment of the knowledge about the sexual networks and behaviors of MSM in Asia, Dowsett, Grierson and McNally concluded that the category of MSM does not correspond to a single social identity in any of the countries they studied.[6] There were no similar traits in all of the MSM population studied, other than them being males and engaging in sex with other men.
In some countries, homosexual relationships may be illegal or taboo, making MSM difficult to reach.[7][8]
The term's precise use and definition has varied with regard totransgender andintersex people, who do not fall neatly into binary sex categories.[9]
Historically,anal sex has been popularly associated with male homosexuality and MSM. However, many[clarification needed] MSM do not engage in anal sex, and may engage inoral sex,frotting ormutual masturbation instead.[10][11][12] Among men who have anal sex with other men, the insertive partner may be referred to as thetop, the one being penetrated may be referred to as thebottom, and those who engage in either role may be referred to asversatile[13]—with those who do not prefer/practice anal sex being referred to asside.
Number of sexual partners
A 2007 study reported that two large population surveys found "the majority of gay men had similar numbers of unprotected sexual partners annually as straight men and women."[14][15] According to the 2013NATSAL (a representative population study in the UK), MSM typically had 17 lifetime sexual partners (median), which included all forms of sexual contact including oral and anal sex.[16] An epidemiological article inThe BMJ reported that national probability surveys like the NATSAL have been found to better reflect the population of MSM but are limited by their smaller samples of MSM.Convenience sample surveys recruit larger samples of MSM but tend to over-represent MSM identifying as gay and reporting more sexual risk behaviors.[17]
Among men who have anal sex with other men,anal sex without use of a condom is considered to be high-risk for STI transmission. A person who inserts their penis into an infected partner is at risk because sexually transmitted infections (STIs) can enter through theurethra or through small cuts, abrasions, or open sores on the penis. Also, condoms are more likely to break during anal sex than during vaginal sex. Thus, even with a condom, anal sex can be risky.[18][19][20]
Acquired immune deficiency syndrome (AIDS) is a disease of the humanimmune system caused by thehuman immunodeficiency virus (HIV).[21][22][23] HIV can infect anybody, regardless of sex, ethnicity, orsexual orientation.[24] Worldwide, an estimated 5–10% of HIV infections are the result of men having sex with men.[25] However, in manydeveloped countries, more HIV infections are transmitted by men having sex with men than by any other transmission route.[24] In the United States, "men who have had sex with men since 1977 have an HIV prevalence (the total number of cases of a disease that are present in a population at a specific point in time) 60 times higher than the general population".[26]
In 2007, the largest estimated proportion of HIV/AIDS diagnoses among adults and adolescents in the U.S. were men who have sex with men (MSM). While this category is only 2% of the U.S. population[27] they accounted for 53% of the overall diagnoses and 71% among men. According to a 2010 federal study, one in five men who have sex with men are HIV positive and nearly half do not realize it.[28]
According to a CDC study, HIV prevalence in the MSM population of the U.S. varies widely by ethnicity. "As many as 46% of black MSM have HIV" while "the HIV rate is estimated at 21% for white MSM and 17% for Hispanic MSM."[29][30][31] In the United States from 2001 to 2005, the highest transmission risk behaviors were sex between men (40–49% of new cases) and high risk heterosexual sex (32–35% of new cases).[32] HIV infection is increasing at a rate of 12% annually among 13–24-year-old American men who have sex with men.[33][34][35] Experts attribute this to "AIDS fatigue" among younger people who have no memory of the worst phase of the epidemic in the 1980s and early 1990s, as well as "condom fatigue" among those who have grown tired of and disillusioned with the unrelentingsafer sex message. The increase may also be because of new treatments.[33] In developing countries, HIV infection rates have been characterized as skyrocketing among MSM.[36] Studies have found that less than 5% of MSM in Africa, Asia, and Latin America have access to HIV-related health care.[36]
Syphilis (caused by infection withTreponema pallidum) is passed from person to person through direct contact with a syphilis sore; these occur mainly on the external genitals, or in the vagina, anus, or rectum.[48] Sores also can occur on the lips and in the mouth.[48] Transmission of the organism occurs during vaginal, anal, or oral sex.[48] In 2006, 64% of the reported cases in the United States were among men who have sex with men.[48] This is consistent with a rise in the incidence of syphilis among MSM in other developed nations, attributed by Australian and UK authors to increased rates of unprotected sex among MSM.[49][50]
Genital human papillomavirus (HPV) is a common virus that most sexually active people in the U.S. will have at some time in their lives.[51] It is passed on through genital contact and is also found on areas that condoms do not cover.[51] Most men who get HPV of any type never develop any symptoms or health problems.[51] Some types of HPV can cause genital warts, penile cancer, or anal cancer.[51] MSM and men with compromisedimmune systems are more likely than other men to develop anal cancer.[51] The incidence of anal cancer among HIV‐positive MSM is nine times higher than among HIV‐negative MSM, even inantiretroviral therapy. HIV-negative MSM has a higher incidence than the general population.[52] Men with HIV are also more likely to get severe cases of genital warts that are hard to treat.[51][53][54]
Though not commonly classified as anSTI,giardiasis can be transmitted between gay men,[55] and it can be responsible for severe weight loss and death for individuals who have compromised immune systems, especially HIV.[56]
Mental health
According to theU.S. Centers for Disease Control, the majority of gay and bisexual men have and maintain good mental health, though research has shown that they are at greater risk for mental health problems. Stigma andhomophobia can have negative consequences on health. Compared to other men, gay and bisexual men have a higher chance of havingdepression andanxiety disorders.[57]
Mpox
In the United States,Mpox has been shown to disproportionately affect men who have sex with men.[58]
Prevalence
A 2024 meta-analysis in the United States of population surveys found that 3.3% of men reported having sex with another man during the past year, 4.7% in the previous 5 years, and 6.2% in their lifetime.[59]
Many countries impose restrictions on donating blood for men who have or have had sex with men, as well as their female sexual partners. Similar restrictions in many countries also prohibit donation of tissues such ascorneas by men who have sex with men, often with far longer deferral periods than for MSM blood donors.[60] Most national standards require direct questioning regarding a donor's sexual history, but the length of deferral varies.
^Glick M, Muzyka BC, Salkin LM, Lurie D (May 1994). "Necrotizing ulcerative periodontitis: a marker for immune deterioration and a predictor for the diagnosis of AIDS".J. Periodontol.65 (5):393–7.doi:10.1902/jop.1994.65.5.393.PMID7913962.
^Operario D, Burton J, Underhill K, Sevelius J (January 2008). "Men who have sex with transgender women: challenges to category-based HIV prevention".AIDS Behav.12 (1):18–26.doi:10.1007/s10461-007-9303-y.PMID17705095.
^ab"2009 AIDS epidemic update". Joint United Nations Programme on HIV/AIDS and World Health Organization. November 2009. Archived fromthe original on September 28, 2011. RetrievedSeptember 28, 2011.
Zhongxin, Sun; Farrer, James; Choi, Kyung-hee (April 2006). "Sexual Identity Among Men Who Have Sex with Men in Shanghai".China Perspectives.2006 (2).doi:10.4000/chinaperspectives.598.
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