Men who have sex with men (MSM), also known as males who have sex with males, are male persons who engage in sexual activity with members of the same sex, regardless of how they identify themselves. They may identify as gay, homosexual, bisexual, pansexual, heterosexual, or dispense with sexual identification altogether.
The term MSM was created in the 1990s by epidemiologists to study the spread of disease among men who have sex with men, regardless of identity. The term MSM is often used in medical literature and social research to describe such men as a group for research studies without considering issues of self-identification. It does not describe any specific sexual activity, and which activities are covered by the term depends on context.
The term MSM had been in use in public health discussions, especially in the context of HIV/AIDS, since 1990 or earlier, but the coining of the initialism by Glick et al. in 1994 "signaled the crystallization of a new concept." This behavioral concept comes from two distinct academic perspectives. First, it was pursued by epidemiologists 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 gay or bisexual is not necessarily sexually active with men, and someone who identifies as straight might be sexually active with men. Second, its usage is tied to criticism of sexual identity terms prevalent in social construction literature which typically rejected the use of identity-based concepts across cultural and historical contexts. The Huffington Post postulates that the term MSM was created by Cleo Manago, the man who is also credited for coining the term same gender loving (SGL).
MSM are not limited to small, self-identified, and visible sub-populations. MSM and gay refer to different things: behaviors and social identities. MSM refers to sexual activities between men, regardless of how they identify, whereas gay 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, whereas homosexual is used in formal contexts, though the terms are not entirely interchangeable. Men who are non-heterosexual or questioning may identify with all, none, a combination of these, or one of the newer terms indicating a similar sexual, romantic, and cultural identity like bi-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. There were no similar traits in all of the MSM population studied, other than them being males and engaging in sex with other men.
The term's precise use and definition has varied with regard to trans women, people born either biologically male or with ambiguous genitalia who self-identify as female. Some sources consider trans women who have sex with men to be MSM, others consider women who are trans "alongside" MSM, and others are internally inconsistent (defining transgender women to be MSM in one place but referring to "MSM and transgender" in another).
Determining the number of men who have ever had sex with another man is difficult. Worldwide, at least 3% of men, and perhaps as high as 16% of men, have had sex at least once with a man. These figures include victims of sexual abuse in addition to men who regularly or voluntarily have sex with men.
In the U.S., among men aged 15 to 44, an estimated 6% have engaged in oral or anal sex with another man at some point in their lives, and about 2.9% have had at least one male sexual partner in the previous 12 months.
Historically, anal sex has been popularly associated with male homosexuality and MSM. However, many MSM do not engage in anal sex, and may engage in oral sex, frotting or mutual masturbation instead. Among men who have anal sex with other men, the insertive partner may be referred to as the top, the one being penetrated may be referred to as the bottom, and those who enjoy either role may be referred to as versatile.
The examples and perspective in this section may not represent a worldwide view of the subject. (January 2018) (Learn how and when to remove this template message)
Since LGBT people began to organize for their social and legal rights[examples needed], access to equal health care[clarification needed] has remained an important but often not primary issue. LGBT-specific health organizations have been formed, including charities educating on specific issues, health clinics, and even professional organizations for LGBT people and their allies. Many of them have advocated for specific changes to various governmental practices, and the ongoing effort[needs update] to legalize same-sex marriage often includes examples of LGBT people unable to secure health coverage equivalent to that of their heterosexual counterparts. The United States Department of Health and Human Services announced in 2012 that the Affordable Care Act (ACA) would offer new protections, including a ban on insurers discriminating against LGBT persons. The ACA also provided funding for community-based preventive health programs and measures to combat HIV-related health disparities.[needs update]
Since medical literature began to describe homosexuality, it has often been approached from a view that assumed or sought to find an inherent psychopathology as the root cause. Much literature on mental health and homosexuals centered on examples of their depression, substance abuse, and suicide. Although these issues exist among non-heterosexuals, discussion about their causes shifted after homosexuality was removed from the Diagnostic and Statistical Manual of Mental Disorders (DSM) in 1973. Instead, social ostracism, legal discrimination, internalization of negative stereotypes, and limited support structures were regarded as indications of the issues faced by homosexuals in Western societies in the late 20th century, which often adversely affected their mental health. Even in a country with a tolerant climate regarding homosexuality such as Sweden, same-sex married individuals evidence a higher risk for suicide -- almost three times higher, than other married individuals.
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." Among men who have anal sex with other men, anal sex without use of a condom is considered to be very risky behavior. A person who inserts their penis into an infected partner is at risk because sexually transmitted diseases (STDS/STIs) can enter through the urethra 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.
Acquired immune deficiency syndrome (AIDS) is a disease of the human immune system caused by the human immunodeficiency virus (HIV). HIV can infect anybody, regardless of sex, ethnicity, or sexual orientation. Worldwide, an estimated 5-10% of HIV infections are the result of men having sex with men. However, in many developed countries, more HIV infections are transmitted by men having sex with men than by any other transmission route. 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".
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 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 don't realize it.
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." In the United States from 2001-2005, the highest transmission risk behaviors were sex between men (40-49% of new cases) and high risk heterosexual sex (32-35% of new cases). HIV infection is increasing at a rate of 12% annually among 13-24-year-old American men who have sex with men. 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 unrelenting safer sex message. The increase may also be because of new treatments. In developing countries, HIV infection rates have been characterized as skyrocketing among MSM. Studies have found that less than 5% of MSM in Africa, Asia, and Latin America have access to HIV-related health care.
Hepatitis B is a disease caused by hepatitis B virus (HBV) which infects the liver of hominoidea, including humans, and causes an inflammation called hepatitis. The disease has caused epidemics in parts of Asia and Africa, and it is endemic in China. About a third of the world's population, more than 2 billion people, have been infected with HBV. Transmission of HBV results from exposure to infectious blood or body fluids containing blood. Possible forms of transmission include (but are not limited to) unprotected sexual contact, blood transfusions, re-use of contaminated needles and syringes, and vertical transmission from mother to child during childbirth. HBV can also be transmitted between family members within households, possibly by contact of non-intact skin or mucous membrane with secretions or saliva containing the virus. However, at least 30% of reported hepatitis B cases among adults cannot be associated with an identifiable risk factor.
Syphilis (caused by infection with Treponema 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. Sores also can occur on the lips and in the mouth. Transmission of the organism occurs during vaginal, anal, or oral sex. In 2006, 64% of the reported cases in the United States were among men who have sex with men. 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.
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. It is passed on through genital contact and is also found on areas that condoms do not cover. Most men who get HPV of any type never develop any symptoms or health problems. Some types of HPV can cause genital warts, penile cancer, or anal cancer. MSM and men with compromised immune systems are more likely than other men to develop anal cancer. The incidence of anal cancer among HIV-positive MSM is 9 times higher than among HIV-negative MSM, even in antiretroviral therapy. HIV-negative MSM has a higher incidence than the general population. Men with HIV are also more likely to get severe cases of genital warts that are hard to treat.
Though not commonly classified as an STI, giardiasis can be transmitted between gay men, and it can be responsible for severe weight loss and death for individuals who have compromised immune systems, especially HIV.
Many countries impose restrictions on donating blood for men who have or have had sex with men, as well as their female sexual partners--see the maps. Most national standards require direct questioning regarding a donor's sexual history, but the length of deferral varies.
However, the risk for invasive anal squamous carcinoma, which is believed to be caused by certain types of sexually transmitted human papilloma viruses, notably type 16, was significantly 31-fold elevated at a crude incidence of 25.6 per 100,000 person-years.