Abstract

WEAX0206 - Oral Abstract Session

Hormonal contraceptive use and risk of HIV-1 transmission: a prospective cohort analysis

Presented by Renee Heffron (United States).

R. Heffron¹, D. Donnell², H. Rees³, C. Celum⁴, E. Were⁵, N. Mugo⁶, G. de Bruyn⁷, E. Nakku-Joloba⁸, K. Ngure⁶, J. Kiarie⁶, J. Baeten⁴, Partners in Prevention HSV/HIV Transmission team

¹University of Washington, Epidemiology, Global Health, Seattle, United States, ²Fred Hutchinson Cancer Research Center, Seattle, United States, ³University of the Witwatersrand, Reproductive Health Research Unit, Johannesburg, South Africa, ⁴University of Washington, Global Health, Medicine and Epidemiology, Seattle, United States, ⁵Moi University, Reproductive Health, Eldoret, Kenya, ⁶Kenyatta National Hospital, Nairobi, Kenya, ⁷University of the Witwatersrand, Perinatal HIV Research Unit, Soweto, South Africa, ⁸New Malago Hospital, Kampala, Uganda

Background: Hormonal contraception, including daily oral pills and long-acting injectable methods, are used widely but their effects on HIV-1 risk are unclear.
Methods: We prospectively followed 3790 heterosexual HIV-1 serodiscordant couples (in which one partner was HIV-1 seropositive and the other seronegative) from 7 African countries for up to 24 months. Among hormonal contraceptive users and nonusers, we compared rates of HIV-1 acquisition in women and HIV-1 transmission from women to men using multivariate Cox proportional hazards regression and marginal structural modeling.
Results: Among 1314 couples in which the HIV-1 seronegative partner was female, HIV-1 acquisition rates were 6.61 and 3.78 per 100 person-years in women currently using and not using hormonal contraception (adjusted hazard ratio [HR] 1.98, 95% confidence interval [CI] 1.06-3.68, p=0.03). Among 2476 couples in which the HIV-1 seronegative partner was male, HIV-1 transmission rates from women to men were 2.61 and 1.51 per 100 person-years in those whose partners currently used versus did not use hormonal contraception (adjusted HR 1.97, 95% CI 1.12-3.45, p=0.02). Both injectable and oral hormonal contraceptive methods were associated with increased HIV-1 risk, although subgroup analyses were statistically significant only for injectable contraception. Results from marginal structural model analyses were consistent with those from the Cox proportional hazards regression. Genital HIV-1 RNA concentrations were significantly higher in HIV-1 seropositive women using hormonal contraception than those using no contraception, suggesting a potential mechanism for increased transmission risk from women to men.
Conclusion: Women should be counseled about potential increased risk of HIV-1 acquisition and transmission with hormonal contraception, particularly injectable methods, and about the importance of dual protection with condoms to decrease HIV-1 risk. Strategies to encourage use of long-acting contraceptive methods with lower doses of exogenous hormones or non-hormonal methods (i.e. intrauterine devices) should be promoted.