Updated August 24, 2015.
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Definition: Men Who Have Sex With Men (MSM) is the term used to categorize males who engage in sexual activity with other males, regardless of how they identify themselves. The term was created in the 1990s by epidemiologists as a surveillance tool to better identify the route of HIV transmission and spread of the disease through male-male sexual activity.
Prior to this, researchers were limited by the identity-based analyses—whereby men who identified as "gay" or "bisexual" weren't necessarily sexually active, while those who identified as "straight" might be sexually active with other men.
The term "MSM" instead focuses on behavior rather than cultural or social self-identification, thereby providing a clearer picture of HIV prevalence (and, in turn, a better understanding of the implications related to HIV prevention).
Studies vary by community and culture, but research conducted by the New York City Department of Health and Mental Hygiene revealed that, of 4,200 men interviewed by telephone:
- Nearly one in ten who identified as "straight" had sex exclusively with other men.
- 70% of married men who identified as "straight" engaged in male-male sexual activity at one time or another.
- 10% of married men who identified as "straight" had reported same-sex behavior during the course of the previous 12 months.
The HIV/AIDS Channel of About.com is pleased to have been named one the "Best HIV/STD Health Blogs" of 2015 by the editors of San Francisco-based Healthline.
Source:
Pathela, P.; Hajat, A.; Schillinger, J.; et al. "Discordance between Sexual Behavior and Self-Reported Sexual Identity: A Population-Based Survey of New York City Men."Annals of Internal Medicine. September 19, 2009; 145(6):416-425.
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