The use of hormonal contraception leads to a small but significant increase in the shedding of HIV-infected cells in the cervix, even though both cervical secretion and blood HIV viral load levels remained unchanged, according to a prospective study involving over 200 HIV-positive women in Kenya. The study was conducted between August 1996 and September 1998, and is published in the January 23rd edition of AIDS.
A previous meta-analysis of over 20 studies found that use of oral or injected hormonal contraception led to an increased susceptibility to HIV. Further, one cross-sectional study found that the infectivity of HIV-positive women was increased by the use of oral or injected contraceptives, while another cross-sectional study found no such association
To provide a more definitive answer on whether hormonal contraceptives increase the infectivity of HIV-positive women, investigators from the US and Kenya conducted a prospective study, collecting cervical secretions before and after the initiation of oral or injectable contraceptives. A qualitative assay was used to detect the presence of HIV proviral DNA, a marker of HIV-infected cells, and a standard quantitative assay was used to measure HIV RNA. Plasma viral load was also measured.
A total of 213 women were recruited to the study. Median age was 25 years, and at baseline the median CD4 cell count was 36 cells/mm3 indicating a high degree of immune suppression in many women.
A variety of hormonal contraceptives were being used by the women. The most popular option was an injectable contraceptive, used by 48% of women, 25% used a low dose oral contraceptive, 24% used a progesterone-only oral contraceptive, and 3% a high-dose oral contraceptive before the low-dose option became available.
Median follow-up was for 42 days. At baseline, 42% had HIV-infected cells detected using the HIV-DNA assay. This increased to 52% after the initiation of hormonal contraception, a statistically significant increase (p=0.03). An increase in the prevalence of HIV-infected cells was noted for all types of hormonal contraception, but these were not statistically significant as the number involved in the study did not allow sufficient statistical power.
At baseline, 82% of women had HIV RNA present in their cervical samples and this increased to 86% after the initiation of hormonal contraception. However, this increase did not have statistical significance (p=0.18). Plasma HIV viral load remained stable at approximately 60,000 copies/mL at baseline and after starting hormonal contraception.
”In this prospective study, women initiating hormonal contraception demonstrated a modest but significant increase in the prevalence of HIV-1 infected cells…and a slight increase in the prevalence of HIV-1 RNA, although this was not statistically significant.” This suggests to the authors that "the increase in infected cells in cervical secretions may reflect an influx of infected cells from systemic compartments rather than changes in local virus replication.”
The investigators conclude that “hormonal contraception may increase the infectivity of HIV…infected women to uninfected partners, thus providing another reason for barrier contraception for partner protection.”
Further information on this website
Hormonal contraceptives increase risk of HIV infection - news story
Wang CC et al. The effect of hormonal contraception on genital tract shedding of HIV-1. AIDS 18: 205 -209, 2004.