Use of injectable hormonal contraception and HSV-2 acquisition in a cohort of female sex workers in Vancouver, Canada.
OBJECTIVE
Increased risk of herpes simplex virus 2 (HSV-2) has been proposed as a possible indirect pathway through which hormonal contraceptives (specifically depot medroxyprogesterone acetate (DMPA)) may increase the risk of HIV acquisition among women. We investigated the effects of DMPA on HSV-2 acquisition among female sex workers.


METHODS
Longitudinal data were drawn from a prospective cohort of sex workers in Vancouver, Canada. The primary outcome was HSV-2 seroconversion. Extended Cox regression analyses were used to model the independent effect of DMPA use on HSV-2 acquisition.


RESULTS
Between January 2010 and February 2014, 149 HSV-2 seronegative women were enrolled, contributing to 228 person-years (py) of follow-up. Of these, 19 (13.3%) reported DMPA use. There were 39 HSV-2 seroconversions (12 among DMPA users and 27 among non-users) over the study period (median follow-up of 18.6 months (IQR 8.4-29.9)), resulting in an overall incidence rate of 17.1 cases per 100 py (95% CI 12.4 to 23.6). Incidence rates were higher among DMPA users (57.4 cases per 100 py, 95% CI 31.4 to 105.0) compared with non-users (13.1 cases per 100 py, 95% CI 8.9 to 19.1). After adjusting for key confounders, use of DMPA remained an independent predictor of HSV-2 acquisition (adjusted HR 4.43, 95% CI 1.90 to 10.35).


CONCLUSIONS
The high observed incidence rates of HSV-2, together with a strong association between DMPA exposure and HSV-2 acquisition, raise serious concerns about the provision of optimal reproductive and sexual healthcare to sex workers in this setting. Given the known links between HSV-2 and HIV, our findings underscore the need for further research to better understand the potential association between DMPA and increased risk of HSV-2 and other STIs to help inform the development of safer reproductive choices for women worldwide.
British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada.|Division of AIDS, Department of Medicine, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada.
M Eugenia
ME
Socías
British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada.
Putu
P
Duff
British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada.|School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada.
Jean
J
Shoveller
British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada.|Division of AIDS, Department of Medicine, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada.
Julio S G
JSG
Montaner
British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada.
Paul
P
Nguyen
School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada.
Gina
G
Ogilvie
British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada.|Division of AIDS, Department of Medicine, University of British Columbia, St. Paul's Hospital, Vancouver, British Columbia, Canada.|School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada.
Kate
K
Shannon
D000328:Adult; D001955:British Columbia / Q000453:epidemiology; D015331:Cohort Studies; D003268:Contraception Behavior / Q000706:statistics & numerical data; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006558:Herpes Genitalis / Q000453:epidemiology / Q000635:transmission*; D006801:Humans; D015994:Incidence; D007267:Injections / Q000009:adverse effects; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage* / Q000009:adverse effects; D011446:Prospective Studies; D060386:Sex Workers; D055815:Young Adult
D003271:Contraceptive Agents, Female; D017258:Medroxyprogesterone Acetate
HIV; HORMONAL CONTRACEPTION; HSV