{
  "abstract": "Objectives Sexual decision-making and sexually transmitted infection (STI) prevention are influenced not only by individuals’ characteristics but also by those of their partners and their relationship with each other. To inform STI prevention and understand transmission dynamics, we aimed to understand sexual partnership demographic assortativity, sexual behaviour, communication and concurrency among UK-resident gay, bisexual and other men who have sex with men (GBMSM).Methods With community members and organisations, we codesigned a sexual partnerships module for an annual online cross-sectional community-based survey of UK-resident GBMSM (cisgender/trans/non-binary assigned-male-at-birth) undertaken November–December 2023. We collected data about ≤3 most recent male sex partners since August 2023 and analysed variations in relative demographic characteristics (age, ethnicity), sexual behaviours (practices, condom use, HIV-pre-exposure prophylaxis (HIV-PrEP use)) and sexual health communication by partner type (one-time, established, casual and uncertain).Results 1106 participants described 2342 partners: 12.5%, 20.4%, 9.9% and 57.1% reporting 0, 1, 2 and 3 partners, respectively, of varying combinations. Casual partner types were most reported (43.2%) versus one-time (36.1%), established (13.9%) and uncertain partnerships (6.8%). Concurrency was common with the mean number of ongoing partnerships >1 (1.23, 95% CI 1.17 to 1.30). Age-mixing varied by partner type, from median 2 (established partners) to 10 (one-time partners) years difference.Sexual health communication was highest among established partners. It was two times as common to be unaware of one-time partners’ HIV status (66.8%) and not to have discussed sexual health (65.7%) compared with casual partners (30.0% and 27.2%, respectively). Condom use was low across partner types. HIV-PrEP was always used by HIV-negative participants in two times as many one-time, causal and uncertain partnerships (49.2%, 50.0%, 42.0%) compared with established partnerships (23.3%) involving condomless anal intercourse.Discussion UK-resident GBMSM have diverse types of male sexual partners, varying in their demographic mixing, sexual behaviour and communication, which should be reflected in sexual health promotion and transmission dynamics analyses.",
  "authors": [
    {
      "affiliations": [
        "Department of Infection and Population Health, Institute for Global Health, University College London, London, UK",
        "Health Protection Research Unit (HPRU) in Blood Borne and Sexually Transmitted Infections, National Institute for Health and Care Research (NIHR) UCL in partnership with the UK Health Security Agency (UKHSA), London, England, UK"
      ],
      "name": "Elizabeth Fearon"
    },
    {
      "affiliations": [
        "Department of Infection and Population Health, Institute for Global Health, University College London, London, UK",
        "Health Protection Research Unit (HPRU) in Blood Borne and Sexually Transmitted Infections, National Institute for Health and Care Research (NIHR) UCL in partnership with the UK Health Security Agency (UKHSA), London, England, UK"
      ],
      "name": "David Etoori"
    },
    {
      "affiliations": [
        "Health Protection Research Unit (HPRU) in Blood Borne and Sexually Transmitted Infections, National Institute for Health and Care Research (NIHR) UCL in partnership with the UK Health Security Agency (UKHSA), London, England, UK",
        "Blood Safety, Hepatitis, STIs and HIV Division, UK Health Security Agency, London, UK"
      ],
      "name": "Dana Ogaz"
    },
    {
      "affiliations": [
        "The Love Tank, London, UK"
      ],
      "name": "Benjamin Weil"
    },
    {
      "affiliations": [
        "The Love Tank, London, UK"
      ],
      "name": "Will Nutland"
    },
    {
      "affiliations": [
        "Department of Infection and Population Health, Institute for Global Health, University College London, London, UK",
        "Health Protection Research Unit (HPRU) in Blood Borne and Sexually Transmitted Infections, National Institute for Health and Care Research (NIHR) UCL in partnership with the UK Health Security Agency (UKHSA), London, England, UK"
      ],
      "name": "David Reid"
    },
    {
      "affiliations": [
        "Health Protection Research Unit (HPRU) in Blood Borne and Sexually Transmitted Infections, National Institute for Health and Care Research (NIHR) UCL in partnership with the UK Health Security Agency (UKHSA), London, England, UK",
        "Blood Safety, Hepatitis, STIs and HIV Division, UK Health Security Agency, London, UK"
      ],
      "name": "John Saunders"
    },
    {
      "affiliations": [
        "Department of Infection and Population Health, Institute for Global Health, University College London, London, UK",
        "Health Protection Research Unit (HPRU) in Blood Borne and Sexually Transmitted Infections, National Institute for Health and Care Research (NIHR) UCL in partnership with the UK Health Security Agency (UKHSA), London, England, UK",
        "Blood Safety, Hepatitis, STIs and HIV Division, UK Health Security Agency, London, UK"
      ],
      "name": "Hamish Mohammed"
    },
    {
      "affiliations": [
        "Department of Infection and Population Health, Institute for Global Health, University College London, London, UK",
        "Health Protection Research Unit (HPRU) in Blood Borne and Sexually Transmitted Infections, National Institute for Health and Care Research (NIHR) UCL in partnership with the UK Health Security Agency (UKHSA), London, England, UK"
      ],
      "name": "Catherine H Mercer"
    }
  ],
  "title": "Insights into sexual partners and partnerships among gay, bisexual and other men who have sex with men in the United Kingdom: results from the Reducing Inequalities in Sexual Health (RiiSH) behavioural survey",
  "uid": "8e35d3e6-c5b1-5f37-a728-d35906e98a32"
}