Charles S. Morrison

Hormonal contraception and the risk of HIV acquisition

Background:Combined oral contraceptives (COC) and depot-medroxyprogesterone acetate (DMPA) are among the most widely used family planning methods; their effect on HIV acquisition is not known. Objective:To evaluate the effect of COC and DMPA on HIV acquisition and any modifying effects of other sexually transmitted infections. Methods:This multicenter prospective cohort study enroled 6109 HIV-uninfected women, aged 18–35 years, from family planning clinics in Uganda, Zimbabwe and Thailand. Participants received HIV testing quarterly for 15–24 months. The risk of HIV acquisition with different contraceptive methods was assessed (excluding Thailand, where there were few HIV cases). Results:HIV infection occurred in 213 African participants (2.8/100 woman-years). Use of neither COC [hazard ratio (HR), 0.99; 95% confidence interval (CI), 0.69–1.42] nor DMPA (HR, 1.25; 95% CI, 0.89–1.78) was associated with risk of HIV acquisition overall, including among participants with cervical or vaginal infections. While absolute risk of HIV acquisition was higher among participants who were seropositive for herpes simplex virus 2 (HSV-2) than in those seronegative at enrolment, among the HSV-2-seronegative participants, both COC (HR, 2.85; 95% CI, 1.39–5.82) and DMPA (HR, 3.97; 95% CI, 1.98–8.00) users had an increased risk of HIV acquisition compared with the non-hormonal group. Conclusions:No association was found between hormonal contraceptive use and HIV acquisition overall. This is reassuring for women needing effective contraception in settings of high HIV prevalence. However, hormonal contraceptive users who were HSV-2 seronegative had an increased risk of HIV acquisition. Additional research is needed to confirm and explain this finding.

Hormonal Contraception and the Risk of HIV Acquisition: An Individual Participant Data Meta-analysis:

In a meta-analysis of individual participant data, Charles Morrison and colleagues explore the association between hormonal contraception use and risk of HIV infection in sub-Saharan Africa.

Intravaginal Practices, Bacterial Vaginosis, and HIV Infection in Women: Individual Participant Data Meta-analysis

Pooling of data from 14,874 women in an individual participant data meta-analysis by Nicola Low and colleagues reveals that some intravaginal practices increase the risk of HIV acquisition.

Hormonal Contraception and HIV Acquisition: Reanalysis using Marginal Structural Modeling

Hormonal contraceptives are used widely worldwide; their effect on HIV acquisition remains unresolved. We reanalyzed data from the Hormonal Contraception and HIV Study using marginal structural modeling to reduce selection bias due to time-dependent confounding. Replicating our original analysis closely, we found that depo-medroxyprogesterone acetate (DMPA) but not combined oral contraceptive (COC) was associated with increased HIV acquisition. Also, young (18–24 years) but not older women who used DMPA and COCs were at increased HIV risk.

The effect of one injection of Depo-Provera® on the human vaginal epithelium and cervical ectopy

Two studies in rhesus monkeys have shown that progesterone implants, Depo-Provera and Norplant, were associated with vaginal thinning. Progesterone implants have also been associated with an increased risk of simian immunodeficiency virus (SIV) acquisition. This study in 16 women was done to assess vaginal epithelial thickness and number of cell layers from biopsies taken in the untreated follicular and luteal phases, and at 1 month and 3 months after administration of Depo-Provera. There was no significant change over time in either parameter from biopsies obtained in the luteal phase compared with those at either time after Depo-Provera administration. There was also no change in the mean number of Langerhans cells in vaginal wall specimens and no change in cervical ectopy. It appears that women do not respond to exogenous progestins with the dramatic vaginal thinning seen in rhesus monkeys.

Hormonal contraceptive use, cervical ectopy, and the acquisition of cervical infections

Background and Objectives: Several previous studies have suggested that hormonal contraception could be associated with increased risk of cervical infections. However, few high-quality prospective studies have examined this relationship. Goal: The goal of this study was to measure the effect of oral contraceptives (OC) and depot-medroxyprogesterone acetate (DMPA) on the acquisition of cervical chlamydial and gonococcal infections. Study: Women attending 2 reproductive health centers in Baltimore, MD, were enrolled into a prospective cohort study. Participants were 15 to 45 years and were initiating OCs or DMPA or not using hormonal contraception. Interviews, physical examinations, and testing for incident cervical infections were conducted at 3, 6, and 12 months. Results: The analysis included 819 women. Most were single (77%) and nulliparous (75%); 43% were black. Median age was 22 years. During the study, 45 women acquired a chlamydial or gonococcal infection (6.2 per 100 women-years). DMPA use (hazard ratio [HR], 3.6; 95% confidence interval [CI], 1.6–8.5), but not OC use (HR, 1.5; 95% CI, 0.6–3.5), was significantly associated with increased acquisition of cervical infections after adjusting for other risk factors. Cervical ectopy was not an important mediator of cervical infection risk. Conclusions: DMPA use, but not OC use, appeared to be significantly associated with increased acquisition of cervical chlamydial and gonococcal infections.

Bacterial vaginosis and vaginal yeast, but not vaginal cleansing, increase HIV-1 acquisition in African women

Objective:To evaluate interrelationships between bacterial vaginosis (BV), vaginal yeast, vaginal practices (cleansing and drying/tightening), mucosal inflammation, and HIV acquisition. Methods:A multicenter, prospective, observational cohort study was conducted, enrolling 4531 HIV-negative women aged 18 to 35 years attending family planning clinics in Zimbabwe and Uganda. Participants were tested for HIV and reproductive tract infections and were interviewed about vaginal practices every 3 months for 15 to 24 months. BV was measured by Gram stain Nugent scoring, vaginal yeast by wet mount, and mucosal inflammation by white blood cells on Gram stain. Results:HIV incidence was 4.12 and 1.53 per 100 woman-years of follow-up in Zimbabwe and Uganda, respectively (a total of 213 incident infections). Women with BV or vaginal yeast were more likely to acquire HIV, especially if the condition was present at the same visit as the new HIV infection and the visit preceding it (hazard ratio [HR] = 2.50, 95% confidence interval [CI]: 1.68 to 3.72 and HR = 2.97, 95% CI: 1.67 to 5.28 for BV and yeast, respectively). These relationships did not seem to be mediated by mucosal inflammation. Vaginal drying/tightening was associated with HIV acquisition in univariate (HR = 1.49, 95% CI: 1.03 to 2.15) but not multivariate models. Vaginal cleansing was not associated with HIV acquisition. Conclusions:BV and yeast may contribute more to the HIV epidemic than previously thought.

Is the intrauterine device appropriate contraception for HIV-1-infected women?

Objective To assess whether the risk of complications is higher in HIV‐1‐infected women compared with non‐infected women in the two years following insertion of the intrauterine contraceptive device.

Disentangling contributions of reproductive tract infections to HIV acquisition in African women.

Objective: To estimate the effects of reproductive tract infections (RTIs) on HIV acquisition among Zimbabwean and Ugandan women. Methods: A multicenter prospective observational cohort study enrolled 4439 HIV-uninfected women aged 18 to 35 attending family planning clinics in Zimbabwe and Uganda. Participants were interviewed, and tested for HIV and RTIs every 3 months for 15 to 24 months. They received HIV risk reduction counseling, male condoms, and treatment for curable RTIs. Results: Despite HIV risk reduction counseling and regular screening and treatment for RTIs, the HIV incidence did not decline during the study. Positive HSV-2 serostatus at baseline (hazard ratio [HR] = 3.69, 95% confidence interval = 2.45–5.55), incident HSV-2 (HR = 5.35, 3.06–9.36), incident Neisseria gonorrhoeae (HR = 5.46, 3.41–8.75), and altered vaginal flora during the study (bacterial vaginosis [BV]: HR = 2.12, 1.50–3.01; and intermediate flora: HR = 2.02, 1.39–2.95) were independently associated with HIV acquisition after controlling for demographic and behavioral covariates and other RTIs (Treponema pallidum, Chlamydia trachomatis, Trichomonas vaginalis, and vaginal yeasts). For N. gonorrhoeae, C. trachomatis, T. vaginalis, and vaginal yeasts, the risk of HIV acquisition increased when the infection was identified at the visit before the HIV-detection visit or with the duration of infection. Population attributable risk percent (PAR%) calculations show that HSV-2 contributes most to acquisition of new HIV infections (50.4% for baseline HSV-2 and 7.9% for incident HSV-2), followed by altered vaginal flora (17.2% for bacterial vaginosis and 11.8% for intermediate flora). Conclusions: A substantial proportion of new HIV infections in Zimbabwean and Ugandan women are attributable to RTIs, particularly HSV-2 and altered vaginal flora.

Incident and prevalent herpes simplex virus type 2 infection increases risk of HIV acquisition among women in Uganda and Zimbabwe

Background:An association has been demonstrated between herpes simplex type 2 (HSV-2) and HIV infection among men, but prospective studies in women have yielded mixed results. Objective:To estimate the effects of prevalent and incident HSV-2 infection on subsequent HIV acquisition among women in two African countries. Design:Prospective cohort study. Methods:HSV-2 and HIV serostatus were evaluated at enrollment and quarterly for 15–24 months among 4531 sexually active, HIV-uninfected women aged 18–35 years from Uganda and Zimbabwe. The association between prior HSV-2 infection and HIV acquisition was estimated using a marginal structural discrete survival model, adjusted for covariates. Results:HSV-2 seroprevalence at enrollment was 52% in Uganda and 53% in Zimbabwe; seroincidence during follow-up was 9.6 and 8.8/100 person-years in Uganda and Zimbabwe, respectively. In Uganda, the hazard ratio (HR) for HIV was 2.8 [95% confidence interval (CI), 1.5–5.3] among women with seroprevalent HSV-2 and 4.6 (95% CI, 1.6–13.1) among women with seroincident HSV-2, adjusted for confounding. In Zimbabwe, the HR for HIV was 4.4 (95% CI, 2.7–7.2) among women with seroprevalent HSV-2, and 8.6 (95% CI, 4.3–17.1) among women with seroincident HSV-2, adjusted for confounding. The population attributable risk percent for HIV due to prevalent and incident HSV-2 infection was 42% in Uganda and 65% in Zimbabwe. Conclusions:HSV-2 plays an important role in the acquisition of HIV among women. Efforts to implement known HSV-2 control measures, as well as identify additional measures to control HSV-2, are urgently needed to curb the spread of HIV.