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.
Conclusion: 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.
aDepartment of Obstetrics and Gynaecology, Kenyatta National Hospital
bInstitute of Tropical Medicine and Infectious Diseases, Jomo Kenyatta University, Nairobi, Kenya
cDepartment of Epidemiology
dDepartment of Global Health
eDepartment of Medicine, University of Washington, Seattle, USA
fDepartment of Obstetrics and Gynaecology, University of Nairobi, Nairobi, Kenya
gDepartment of Obstetrics, Gynecology and Reproductive Sciences, University of California San Francisco, San Francisco, USA
hKenya Medical Research Institute, Nairobi, Kenya
iWits Reproductive Health and HIV Institute, University of the Witwatersrand, Johannesburg, South Africa
jDepartment of Reproductive Health, Moi University, Eldoret, Kenya.
Correspondence to Jared M. Baeten, University of Washington, 325 Ninth Avenue, Box 359927, Seattle, WA 98104, USA. Tel: +1 206 520 3808; e-mail: email@example.com
Received 15 June, 2011
Revised 4 November, 2011
Accepted 23 November, 2011