Article Text

Download PDFPDF
Non-monogamy and risk of infection with Chlamydia trachomatis and Trichomonas vaginalis among young adults and their cohabiting partners in Peru
  1. Fredy A Canchihuaman1,4,
  2. Cesar P Carcamo1,
  3. Patricia J Garcia1,
  4. Sevgi O Aral2,
  5. William L H Whittington3,
  6. Stephen E Hawes3,4,
  7. James P Hughes3,5,
  8. King K Holmes3,4,6
  1. 1Universidad Peruana Cayetano Heredia, Lima, Peru
  2. 2Division of STD Prevention, The National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
  3. 3Center for AIDS and STDs, University of Washington, Seattle, Washington, USA
  4. 4Department of Epidemiology, University of Washington, Seattle, Washington, USA
  5. 5Department of Biostatistics, University of Washington, Seattle, Washington, USA
  6. 6Department of Global Health and Medicine, University of Washington, Washington, Seattle, USA
  1. Correspondence to Dr King K Holmes, 325 Ninth Avenue, Box 359931, Seattle, WA 98104, USA; worthy{at}


Objectives To determine how patterns of non-monogamy influence prevalences of sexually transmitted infections (STIs) in individuals and their cohabitating sex partners.

Methods A 2002 survey in 24 Peruvian cities enrolled men and women aged 18–29 years from random household samples. The cohabiting sex partner of each enrolee was also enrolled until approximately 100 couples per city were recruited. Men provided urine and women vaginal swabs or urine for molecular testing for Chlamydia trachomatis and Trichomonas vaginalis; both genders provided blood for serological testing.

Results Among 2099 females and 2052 males providing specimens and behavioural data, 18.2% of males and 2.5% of females reported non-monogamy during the past year. C trachomatis was detected in 121 females (5.8%) and 80 males (4.1%) and T vaginalis in 87 females (4.2%) and 26 males (1.3%). Multivariate analyses showed that C trachomatis infection in females was significantly associated with her male partner's non-monogamy (OR 2.02, CI 1.32 to 3.08) but not significantly with her own non-monogamy; T vaginalis was associated with her own non-monogamy (OR 3.11, CI 1.25 to 7.73) and with her partner's non-monogamy (OR 2.07, CI 1.26 to 3.42). For males, both C trachomatis (OR 2.17, CI 1.29 to 3.69) and T vaginalis (OR 2.49, CI 1.06 to 5.87) were significantly associated only with his own non-monogamy.

Conclusions Among cohabiting couples, male non-monogamy was common and was associated with C trachomatis and T vaginalis infection in himself and in his female partner, whereas female non-monogamy was reported infrequently and was significantly associated only with her own T vaginalis infection. Patterns of non-monogamy may guide public health interventions.

  • Sexually transmitted diseases (STDs)
  • risk factors
  • sexual behaviour
  • sexual networks
  • epidemiology

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Funding This study was supported by the Wellcome Trust-Burroughs Wellcome Fund Infectious Disease Initiative (059131/Z/99/Z, 078835/Z/05/Z, 078835/Z/05/B), the National Institutes of Health/NIAID STD Cooperative Research Center (AI31448), the University of Washington Center for AIDS Research (P30-AI27757), the NIH Fogarty International Center AIDS International Training and Research Program (grant D43-TW00007) and by the Peru ICOHRTA Network for AIDS/TB Research Training (grant U2-RTW007368, U2-RTW007374).

  • Competing interests None.

  • Ethics approval All procedures were approved by institutional review boards at the Universidad Peruana Cayetano Heredia, Lima, Peru, at the US Naval Medical Research Center in Lima, Peru, and at the University of Washington, Seattle, USA.

  • Provenance and peer review Not commissioned; externally peer reviewed.