title: Use of hormonal contraceptives and risk of HIV-1 transmission: a prospective cohort study.
abstract: BACKGROUND
  Hormonal contraceptives are used widely but their effects on HIV-1 risk are unclear. We aimed to assess the association between hormonal contraceptive use and risk of HIV-1 acquisition by women and HIV-1 transmission from HIV-1-infected women to their male partners.
  
  
  METHODS
  In this prospective study, we followed up 3790 heterosexual HIV-1-serodiscordant couples participating in two longitudinal studies of HIV-1 incidence in seven African countries. Among injectable and oral hormonal contraceptive users and non-users, we compared rates of HIV-1 acquisition by women and HIV-1 transmission from women to men. The primary outcome measure was HIV-1 seroconversion. We used Cox proportional hazards regression and marginal structural modelling to assess the effect of contraceptive use on HIV-1 risk.
  
  
  RESULTS
  Among 1314 couples in which the HIV-1-seronegative partner was female (median follow-up 18·0 [IQR 12·6-24·2] months), rates of HIV-1 acquisition were 6·61 per 100 person-years in women who used hormonal contraception and 3·78 per 100 person-years in those who did not (adjusted hazard ratio 1·98, 95% CI 1·06-3·68, p=0·03). Among 2476 couples in which the HIV-1-seronegative partner was male (median follow-up 18·7 [IQR 12·8-24·2] months), rates of HIV-1 transmission from women to men were 2·61 per 100 person-years in couples in which women used hormonal contraception and 1·51 per 100 person-years in couples in which women did not use hormonal contraception (adjusted hazard ratio 1·97, 95% CI 1·12-3·45, p=0·02). Marginal structural model analyses generated much the same results to the Cox proportional hazards regression.
  
  
  CONCLUSIONS
  Women should be counselled about potentially increased risk of HIV-1 acquisition and transmission with hormonal contraception, especially injectable methods, and about the importance of dual protection with condoms to decrease HIV-1 risk. Non-hormonal or low-dose hormonal contraceptive methods should be considered for women with or at-risk for HIV-1.
  
  
  BACKGROUND
  US National Institutes of Health and the Bill & Melinda Gates Foundation.
authors.affiliation: Department of Epidemiology, University of Washington, Seattle, WA, USA.
authors.forename: Renee
authors.initials: R
authors.lastname: Heffron
authors.forename: Deborah
authors.initials: D
authors.lastname: Donnell
authors.forename: Helen
authors.initials: H
authors.lastname: Rees
authors.forename: Connie
authors.initials: C
authors.lastname: Celum
authors.forename: Nelly
authors.initials: N
authors.lastname: Mugo
authors.forename: Edwin
authors.initials: E
authors.lastname: Were
authors.forename: Guy
authors.initials: G
authors.lastname: de Bruyn
authors.forename: Edith
authors.initials: E
authors.lastname: Nakku-Joloba
authors.forename: Kenneth
authors.initials: K
authors.lastname: Ngure
authors.forename: James
authors.initials: J
authors.lastname: Kiarie
authors.forename: Robert W
authors.initials: RW
authors.lastname: Coombs
authors.forename: Jared M
authors.initials: JM
authors.lastname: Baeten
mesh_terms: D000328:Adult; D000351:Africa, Eastern / Q000453:epidemiology; D000353:Africa, Southern / Q000453:epidemiology; D018791:CD4 Lymphocyte Count; D002584:Cervix Uteri / Q000821:virology; D003278:Contraceptives, Oral, Hormonal; D005260:Female; D006679:HIV Seropositivity / Q000453:epidemiology* / Q000276:immunology / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D015994:Incidence; D008297:Male; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012725:Sexual Behavior; D055815:Young Adult
chemical_list: D003278:Contraceptives, Oral, Hormonal