Hormonal Contraceptive Use and HIV-1 Infection in a Population-Based Cohort in Rakai, Uganda

Although Uganda is the first country in sub-Saharan Africa to show a decline in HIV prevalence, current estimates are that 820,000 are living with HIV there. Of those, 51.2 percent are women ages 15-49. Most new infections (84 percent) in Uganda occur through heterosexual transmission. Women are vulnerable in Ugandan society because of their status, lower education, higher unemployment, and weaker negotiating skills within relationships.

The current study assesses whether or not hormonal contraceptives -- one population control method offered by family planning programs in Uganda -- increase susceptibility to and infectiousness of HIV. Past studies on the subject have reached contradictory results.

Hormonal contraceptives cause thinning of the vaginal and cervical mucosa, possibly increasing the likelihood of trauma and increasing the density of HIV target cells. They are also associated with cervical ectopy, thought to be a risk factor for HIV and other STDs. Use of hormonal contraceptives in HIV-infected women is associated with increased HIV shedding into the genital tract, which suggests that hormonal contraceptive users may be more infectious.

"An association between hormonal contraceptives and increased HIV acquisition or transmission is of public health concern, particularly given the need for HIV-infected women to prevent unwanted pregnancy in order to avoid transmission of HIV to their infants," Kiddugavu and colleagues wrote. "The purpose of this study was to examine the association between hormonal contraception and HIV acquisition in a rural population-based cohort in Rakai District, Uganda."

Using data from an ongoing community-based cohort established in 1994 for the Rakai STD Control for AIDS Prevention Trial, the researchers studied 5,117 sexually active HIV-negative women who were surveyed at 10-month intervals between 1994 and 1999. A total of 960 women used some hormonal contraception, either oral or injectable, during the period of observation. Participants ages 20-24 and 25-34 showed the highest use of hormonal contraceptives (19.9 percent and 23.5 percent, respectively). Their use was lowest in adolescents and older women (roughly 10 percent each). The proportion of women using hormonal contraceptives increased with higher levels of education and number of sex partners.

There were 202 HIV cases in the cohort, of whom 159 (78.7 percent) were not using hormonal contraceptives at the time of seroconversion. Twelve (5.9 percent) were on the contraceptive pill, 16 (7.9 percent) used injectable contraception, and 15 (7.4 percent) used condoms. HIV incidence was higher in the younger age groups; in divorced, separated, or widowed women; and in women reporting multiple sex partners, condom use, or genital ulcer disease.

Stating that theirs is the first prospective study to examine the association between hormonal contraceptives and HIV acquisition in a general population -- as opposed to a population of commercial sex workers -- the authors note that they observed no significant association between hormonal contraceptive use and the risk of acquiring HIV, either in unadjusted or adjusted (for age, condom use, number of sexual partners, marital status, contraceptive method, education, and history of genital ulcer disease) analyses.

"We found no overall protective effect against HIV acquisition in women who reported condom use, largely because of the inconsistent nature of condom use," the researchers wrote. "This is supported by other studies, which suggested that only consistent condom use is protective against HIV and STD."

"In conclusion," the researchers stated, "our data and those of other investigations suggest that hormonal contraceptive use is not associated with increased HIV acquisition, and that these methods of family planning can be promoted as effective contraception even in areas with high HIV prevalence.... Family planning providers should be trained to provide HIV/AIDS counseling to clients and should consider promotion of both hormonal methods in conjunction with condoms. Also, HIV counselors should be encouraged to provide family planning services or referral."

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