title: Contraceptive method and pregnancy incidence among women in HIV-1-serodiscordant partnerships.
abstract: BACKGROUND
  Effective contraception reduces unintended pregnancies and is a central strategy to reduce vertical HIV-1 transmission for HIV-1-infected women.
  
  
  METHODS
  Among 2269 HIV-1-seropositive and 1085-seronegative women from seven African countries who were members of HIV-1-serodiscordant heterosexual partnerships and who were participating in an HIV-1 prevention clinical trial, we assessed pregnancy incidence according to contraceptive method using multivariate Andersen-Gill analysis.
  
  
  RESULTS
  Compared with women using no contraceptive method, pregnancy incidence was significantly reduced among HIV-1-seropositive and HIV-1-seronegative women using injectable contraception [adjusted hazard ratio (aHR) 0.24, P = 0.001 and aHR 0.25, P < 0.001, respectively). Oral contraceptives significantly reduced pregnancy risk only among HIV-1-seropositive women (aHR 0.51, P = 0.004) but not seronegative women (aHR 0.64, P = 0.3), and, for both seropositive and seronegative women, oral contraceptive pill users were more likely to become pregnant than injectable contraceptive users (aHR 2.22, P = 0.01 for HIV-1-seropositive women and aHR 2.65, P = 0.09 for HIV-1-seronegative women). Condoms, when reported as being used as the primary contraceptive method, marginally reduced pregnancy incidence (aHR 0.85, P = 0.1 for seropositive women and aHR 0.67, P = 0.02 for seronegative women). There were no pregnancies among women using intrauterine devices, implantable methods or who had undergone surgical sterilization, although these methods were used relatively infrequently.
  
  
  CONCLUSIONS
  Family planning programs and HIV-1 prevention trials need innovative ways to motivate uptake and sustained use of longer acting, less user-dependent contraception for women who do not desire pregnancy.
authors.affiliation: Department of Obstetrics and Gynaecology, Kenyatta National Hospital, Nairobi, Kenya.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Ngure
authors.forename: Renee
authors.initials: R
authors.lastname: Heffron
authors.forename: Nelly R
authors.initials: NR
authors.lastname: Mugo
authors.forename: Connie
authors.initials: C
authors.lastname: Celum
authors.forename: Craig R
authors.initials: CR
authors.lastname: Cohen
authors.forename: Josephine
authors.initials: J
authors.lastname: Odoyo
authors.forename: Helen
authors.initials: H
authors.lastname: Rees
authors.forename: James N
authors.initials: JN
authors.lastname: Kiarie
authors.forename: Edwin
authors.initials: E
authors.lastname: Were
authors.forename: Jared M
authors.initials: JM
authors.lastname: Baeten
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission*; D000328:Adult; D017954:Africa South of the Sahara / Q000453:epidemiology; D003276:Contraceptives, Oral / Q000627:therapeutic use*; D004311:Double-Blind Method; D005193:Family Planning Services; D005260:Female; D006679:HIV Seropositivity / Q000453:epidemiology / Q000635:transmission*; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D007434:Intrauterine Devices / Q000706:statistics & numerical data; D011247:Pregnancy / Q000706:statistics & numerical data*; D011251:Pregnancy Complications, Infectious / Q000517:prevention & control* / Q000821:virology
chemical_list: D003276:Contraceptives, Oral