title: Effectiveness of hormonal contraception in HIV-infected women using antiretroviral therapy.
abstract: OBJECTIVE
  The objective of this study is to assess whether antiretroviral therapy (ART) may diminish the effectiveness of hormonal contraceptive methods.
  
  
  METHODS
  Using data from 5153 HIV-infected women followed prospectively for 1-3 years in three HIV prevention studies in Africa, we compared incident pregnancy rates by contraceptive method (implant, injectable, oral or none) and ART use. Multivariable Cox regression models were used to determine adjusted hazard ratios (aHRs) and test interactions between each method and ART use.
  
  
  RESULTS
  During follow-up, 9% of women ever used implants, 40% used injectables and 14% used oral contraceptives; 31% of women ever used ART, mostly nevirapine (75% of ART users) or efavirenz-based (15%). Among women not using contraception, pregnancy rates were 13.2 and 22.5 per 100 women-years for those on and not on ART, respectively. Implants greatly reduced the incidence of pregnancy among both women on ART [aHR 0.06, 95% confidence interval (95% CI) 0.01-0.45] and not on ART (aHR 0.05, 95% CI 0.02-0.11). Injectables (aHR 0.18 on ART and aHR 0.20 not on ART) and oral contraceptives (aHR 0.37 on ART and aHR 0.36 not on ART) also reduced pregnancy risk, though by lesser degrees. ART use did not significantly diminish contraceptive effectiveness, although all methods showed nonstatistically significant reduced effectiveness when concurrently using efavirenz.
  
  
  CONCLUSIONS
  Hormonal contraceptive methods are highly effective in reducing pregnancy risk in HIV-infected women, including those concurrently using ART. Studies of potential interactions between ART and contraceptives should evaluate real-world effectiveness of contraceptive methods; in this study, implants were the most effective method to prevent pregnancy, even during ART use.
authors.affiliation: aDepartment of Epidemiology bDepartment of Global Health cDepartment of Medicine, University of Washington, Seattle, Washington, USA dDepartment of Obstetrics & Gynaecology, University of Nairobi eSexual, Reproductive, Adolescent and Child Health Research Program, Kenya Medical Research Institute, Nairobi, Kenya fFHI 360, Contraceptive Technology Innovation Department, Durham, North Carolina gDivision of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, USA hDepartment of Reproductive Health, Moi University, Eldoret, Kenya iWits Reproductive Health and HIV Institute (WRHI), University of the Witwatersrand, Johannesburg, South Africa jCenter for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya.
authors.forename: Maria
authors.initials: M
authors.lastname: Pyra
authors.forename: Renee
authors.initials: R
authors.lastname: Heffron
authors.forename: Nelly R
authors.initials: NR
authors.lastname: Mugo
authors.forename: Kavita
authors.initials: K
authors.lastname: Nanda
authors.forename: Katherine K
authors.initials: KK
authors.lastname: Thomas
authors.forename: Connie
authors.initials: C
authors.lastname: Celum
authors.forename: Athena P
authors.initials: AP
authors.lastname: Kourtis
authors.forename: Edwin
authors.initials: E
authors.lastname: Were
authors.forename: Helen
authors.initials: H
authors.lastname: Rees
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Bukusi
authors.forename: Jared M
authors.initials: JM
authors.lastname: Baeten
mesh_terms: D000293:Adolescent; D000328:Adult; D000349:Africa; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods*; D003267:Contraception / Q000379:methods*; D003271:Contraceptive Agents, Female / Q000008:administration & dosage*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D044966:Anti-Retroviral Agents; D003271:Contraceptive Agents, Female