Critical Review: Mechanisms of HIV Transmission in Depo-Provera Users: The Likely Role of Hypoestrogenism

Effects of injectable contraception with depot medroxyprogesterone acetate or norethisterone enanthate on estradiol levels and menstrual, psychological and behavioral measures relevant to HIV risk: The WHICH randomized trial

BACKGROUND

Observational data suggest lower HIV risk with norethisterone enanthate (NET-EN) than with depo-medroxyprogesterone acetate intramuscular (DMPA-IM) injectable contraceptives. If confirmed, a switch between these similar injectable methods would be programmatically feasible and could impact the trajectory of the HIV epidemic. We aimed in this paper to investigate the effects of DMPA-IM and NET-EN on estradiol levels, measures of depression and sexual activity and menstrual effects, relevant to HIV risk; and to ascertain whether these measures are associated with estradiol levels.

METHODS

This open-label trial conducted at two sites in South Africa from 5 November 2018 to 30 November 2019, randomized HIV-negative women aged 18-40 to DMPA-IM 150 mg intramuscular 12-weekly (n = 262) or NET-EN 200 mg intramuscular 8-weekly (n = 259). Data were collected on hormonal, behavioral and menstrual effects at baseline and at 25 weeks (25W).

RESULTS

At 25W, median 17β estradiol levels were substantially lower than at baseline (p<0.001) for both methods: 76.5 pmol/L (interquartile range (IQR) 54.1 to 104.2) in the DMPA-IM group (n = 222), and 69.8 pmol/L (IQR: 55.1 to 89.3) in the NET-EN group (n = 225), with no statistical difference between the two methods (p = 0.450). Compared with DMPA-IM, NET-EN users reported significantly less amenorrhoea, fewer sexual acts, fewer users reporting at least one act of unprotected sex, more condom use with steady partner, more days with urge for sexual intercourse, more days feeling partner does not love her, and more days feeling sad for no reason. We did not find a clear association between estradiol levels and sexual behavior, depression and menstrual effects. Behavioral outcomes suggest less sexual exposure with NET-EN than DMPA-IM. The strength of this evidence is high due to the randomized study design and the consistency of results across the outcomes measured.

CONCLUSIONS

Estradiol levels were reduced to postmenopausal levels by both methods. Secondary outcomes suggesting less sexual exposure with NET-EN are consistent with reported observational evidence of less HIV risk with NET-EN. A randomized trial powered for HIV acquisition is feasible and needed to answer this important question.

TRIAL REGISTRATION

PACTR 202009758229976.

In the name of science: Ethical violations in the ECHO randomised trial

It was in the 1990s, that the possibility of increased transmission of HIV with the use of injectable contraceptive Depo-Provera®, was first flagged in medical literature. This has posed a challenge for its use in countries, particularly in the African region, where the prevalence and transmission rate of HIV is high. In 2015, a randomised 'clinical' trial, the Evidence for Contraceptive Options and HIV Outcomes (ECHO) was launched in four African countries to resolve the question whether the increased risk was causal. Contrary to expectations, the ECHO trial successfully recruited and randomised the specified number of girls/women participants. This paper argues that this was made possible by exercising undue influence, by using incentives, coercive language, and by concealing the real nature of the clinical trial during recruitment. The ECHO trial is unique in subjecting a group of healthy girls/women knowingly to a contraceptive drug with an intention not of finding out whether it is efficacious as a contraceptive, but to find out how risky or life-threatening its use could be. Thus, the ECHO trial has violated one of the central tenets of the Helsinki Declaration by privileging pursuit of knowledge over the interests of the girl/women trial participants from Africa.

Multi-omics analysis of the cervical epithelial integrity of women using depot medroxyprogesterone acetate

Depot medroxyprogesterone acetate (DMPA) is an injectable hormonal contraceptive used by millions of women worldwide. However, experimental studies have associated DMPA use with genital epithelial barrier disruption and mucosal influx of human immunodeficiency virus (HIV) target cells. We explored the underlying molecular mechanisms of these findings. Ectocervical biopsies and cervicovaginal lavage (CVL) specimens were collected from HIV-seronegative Kenyan sex workers using DMPA (n = 32) or regularly cycling controls (n = 64). Tissue samples were assessed by RNA-sequencing and quantitative imaging analysis, whereas protein levels were measured in CVL samples. The results suggested a DMPA-associated upregulation of genes involved in immune regulation, including genes associated with cytokine-mediated signaling and neutrophil-mediated immunity. A transcription factor analysis further revealed DMPA-associated upregulation of RELA and NFKB1 which are involved in several immune activation pathways. Several genes significantly downregulated in the DMPA versus the control group were involved in epithelial structure and function, including genes encoding keratins, small proline-rich proteins, and cell-cell adhesion proteins. Pathway analyses indicated DMPA use was associated with immune activation and suppression of epithelium development, including keratinization and cornification processes. The cervicovaginal microbiome composition (Lactobacillus dominant and non-Lactobacillus dominant) had no overall interactional impact on the DMPA associated tissue gene expression. Imaging analysis verified that DMPA use was associated with an impaired epithelial layer as illustrated by staining for the selected epithelial junction proteins E-cadherin, desmoglein-1 and claudin-1. Additional staining for CD4⁺ cells revealed a more superficial location of these cells in the ectocervical epithelium of DMPA users versus controls. Altered protein levels of SERPINB1 and ITIH2 were further observed in the DMPA group. Identification of specific impaired epithelial barrier structures at the gene expression level, which were verified at the functional level by tissue imaging analysis, illustrates mechanisms by which DMPA adversely may affect the integrity of the genital mucosa.

Sexual transmission accounts for the majority of all new HIV infections in women, and alterations to the mucosal environment of the female genital tract have been associated with an increase in the risk of acquiring HIV. Observational epidemiological studies have implied that the use of the injectable hormonal contraceptive depot medroxyprogesterone acetate (DMPA) may be associated with increased HIV-acquisition. However, a prospective clinical study has not confirmed this association and the controversial findings are currently evaluated in the context of international reproductive health policies. Several studies using various model systems indicate that DMPA affects the integrity of the genital epithelial barrier as well as the mucosal immune system, but the exact mechanisms remain largely unknown. To characterize the effect of DMPA on the genital mucosal environment, we used a multi-omics approach to assess paired genital secretions and cervical tissue samples from long-term regular DMPA users living in Kenya. This unique cohort represents a population at risk of HIV infection in which DMPA is one of the most commonly used hormonal contraceptives. We identified impaired cervical epithelial barrier structures, including DMPA-associated reduction in the expression of cell-cell adhesion molecules, keratins, small proline-rich proteins and a thinner upper epithelial layer with more superficially located CD4⁺ cells. Gene set enrichment pathway analyses indicated DMPA use was associated with immune activation and suppression of epithelium development including keratinization and cornification pathways. Protein analysis identified altered levels of selected anti-proteases. Our findings illustrate mechanisms by which DMPA adversely may affect the integrity of the genital mucosa.

The Effect of Exogenous Sex Steroids on the Vaginal Microbiota: A Systematic Review

Background

Exogenous sex steroids within hormonal contraception and menopausal hormone therapy (MHT) have been used for family planning and management of menopausal symptoms, without consideration of their effects on the vaginal microbiota. This is largely because their use predates our understanding of the importance of the vaginal microbiome on human health. We conducted a systematic review (PROSPERO: CRD42018107730) to determine the influence of exogenous sex steroids, stratified by oestrogen-containing or progestin-only types of contraception, and MHT on the vaginal microbiome, as measured by molecular methods.

Methods

Embase, PubMed and Medline were searched for relevant literature published through to December 1st 2020. Eligible studies reported on the effect of specific exogenous sex steroids on the vaginal microbiome using a molecular method. Data regarding the ‘positive’, ‘negative’ or ‘neutral’ effect of each type of contraceptive or MHT on the vaginal microbiome was extracted and summarised. A positive effect reflected sex steroid exposure that was associated with increased abundance of lactobacilli, a change to, or maintenance of, an optimal vaginal microbiota composition, or a decrease in bacterial diversity (specifically reflecting a low-diversity optimal microbiota state), relative to the control group. An exogenous sex steroid was designated as having a negative effect on the vaginal microbiome if it resulted in opposing effects (i.e. loss of lactobacilli, a non-optimal microbiota state). When no significant change was found, this was considered neutral/inconclusive.

Results

We identified 29 manuscripts reporting on the effect of exogenous sex steroids on the vaginal microbiome; 25 investigating hormonal contraceptives, and 4 investigating MHT. Oestrogen-containing contraception, particularly reflecting the combined oestrogen and progestin-containing contraceptive pill, had a positive effect on the composition of the vaginal microbiota. Progestin-only contraception, particularly reflecting depo-medroxyprogesterone acetate, had mixed effects on the microbiota. Among post-menopausal women using MHT, exogenous oestrogen applied topically was associated with increased prevalence of lactobacilli.

Conclusion

Our findings suggest that oestrogen-containing compounds may promote an optimal vaginal microbiota, which could have clinical applications. The impact of progestin-only contraceptives on the vaginal microbiota is less clear; more data is needed to determine how progestin-only contraceptives contribute to adverse reproductive and sexual health outcomes.

Short Communication:Transgender Women on Feminizing Hormone Therapy Demonstrate a Distinct Rectal Mucosal Transcriptome from Cisgender Men

Among transgender women (TGW), the effects of feminizing hormone therapy use on rectal mucosal (RM) HIV transmission are largely unknown. In this small pilot study, we compared the RM transcriptome in TGW utilizing feminizing hormone therapy with a group of cisgender men who have sex with men (MSM) engaging in condomless receptive anal intercourse (AI) and to a group of cisgender men who had never engaged in AI. There were 498 differentially expressed genes (DEGs) in TGW compared with men who had never engaged in AI, and 154 DEGs compared with the MSM. Among TGW, a unique RM transcriptome was identified that implicated pathways critical for mucosal immune responses, including upregulation of genes that mediate immune cell activation and the production of cytokines and other immune signaling molecules. Furthermore, gene set enrichment analyses identified immune signatures that implicated enrichment of proinflammatory immunological pathways in TGW, specifically involving interferon-α, interleukin-6, and tumor necrosis factor-α signaling, whereas metabolic pathways were shown to be enriched among the cisgender male groups. These findings suggest that TGW have a distinct RM immune environment influenced by the use of feminizing hormones, and consequently, there is an urgent need for further investigation into the immunological effects of gender-affirming hormone therapy and its potential impact on HIV mucosal transmission risk for transgender individuals.

Is the Injectable Contraceptive Depo-Medroxyprogesterone Acetate (DMPA-IM) Associated with an Increased Risk for HIV Acquisition? The Jury Is Still Out

Intramuscular depo-medroxyprogesterone acetate (DMPA-IM) is the most widely used hormonal contraceptive in sub-Saharan Africa. Previous meta-analyses of observational studies found a significant 40%–50% increased risk associated with DMPA-IM use, relative to no contraception or infrequent condom use. This raised substantial concerns, although these studies had important limitations. Consequently, the open-label randomized Evidence for Contraceptive Options and HIV Outcomes trial was conducted, designed primarily to detect a 50% or greater difference in HIV risk between DMPA-IM, the levonorgestrel (LNG) implant, and the copper-intrauterine device. The ECHO study, published in July 2019, concluded that there is no substantial difference in HIV risk among the methods evaluated, and that all three methods are safe and highly effective. In response, the WHO relaxed the Medical Eligibility Criteria for DMPA-IM use among women at high HIV risk in August 2019. However, two of the three comparisons in the ECHO trial could rule out neither a 50% increase nor no change in HIV risk for one contraceptive compared with another. The study had limitations and the results contained considerable uncertainty. They also did not inform on associated HIV risk for any one of the individual methods due to the absence of a control group such as no contraception or only infrequent condom use. The HIV risks associated with LNG implant and copper-IUD relative to no contraception or infrequent condom use are unknown and these cannot be seen as controls, nor did the authors claim them to be. The results will be discussed in the context of their limitations, what they add to the body of work to date on contraception and HIV acquisition, and the implications of the findings and reports thereof for future research and contraceptive choice.

Defining characteristics of genital health in South African adolescent girls and young women at high risk for HIV infection

The genital tract of African women has been shown to differ from what is currently accepted as ‘normal’, defined by a pH≤4.5 and lactobacilli-dominated microbiota. Adolescent girls and young women (AGYW) from sub-Saharan Africa are at high risk for HIV, and we hypothesized that specific biological factors are likely to be influential. This study aimed to compare characteristics of vaginal health in HIV-negative AGYW (16-22-years-old), from two South African communities, to international norms. We measured plasma hormones, vaginal pH, presence of BV (Nugent scoring), sexually transmitted infections (multiplex PCR for Chlamydia trachomatis, Neisseria gonorrhoea, Trichomonas vaginalis, Mycoplasma genitalium) and candidiasis (Gram stain) in AGYW (n = 298) from Cape Town and Soweto. Cervicovaginal microbiota was determined by 16S pyrosequencing; 44 genital cytokines were measured by Luminex; and cervical T-cell activation/proliferation (CCR5, HLA-DR, CD38, Ki67) was measured by multiparametric flow cytometry. 90/298 (30.2%) AGYW were negative for BV, candidiasis and bacterial STIs. L. crispatus and L. iners were the dominant bacteria in cervicovaginal swabs, and the median vaginal pH was 4.7. AGYW with L. crispatus-dominant microbiota (42.4%) generally had the lowest cytokine concentrations compared to women with more diverse microbiota (34/44 significantly upregulated cytokines). Frequencies of CCR5+CD4⁺ T-cells co-expressing CD38 and HLA-DR correlated positively with interleukin (IL)-6, TNF-α, GRO-α, macrophage inflammatory protein (MIP)-1α, and IL-9. While endogenous oestrogen had an immune-dampening effect on IL-6, TNF-related apoptosis-inducing ligand (TRAIL) and IL-16, injectable hormone contraceptives (DMPA and Net-EN) were associated with significantly lower endogenous hormone concentrations (p<0.0001 for oestrogen and progesterone) and upregulation of 34/44 cytokines. Since genital inflammation and the presence of activated CD4+ T cells in the genital tract have been implicated in increased HIV risk in South African women, the observed high levels of genital cellular activation and cytokines from AGYW may point towards biological factors increasing HIV risk in this region.

HIV risk associated with serum medroxyprogesterone acetate levels among women in East and southern Africa

BACKGROUND

Some observational studies have found increased HIV risk associated with self-reported use of injectable depot medroxyprogesterone acetate. Testing blood samples for medroxyprogesterone acetate (MPA), the progestin in depot medroxyprogesterone acetate, permits validation of self-reported data, and exploration of whether potential HIV risk is correlated with MPA levels, which are highest soon after injection.

METHODS

We conducted a case-control study testing archived serum from women who participated in three longitudinal studies of HIV prevention in East and southern Africa. Case samples, from women who acquired HIV, were from visits that occurred at or immediately prior to the first evidence of HIV infection. Secondary analyses restricted to case samples collected within 15 and 30 days of the estimated date of HIV infection. Matched control samples were from women who remained HIV uninfected. We used multivariable conditional logistic regression to compare exogenous hormone levels, quantified through mass spectrometry, among cases and controls.

RESULTS

When restricted to cases with samples collected within 15 days or less of estimated date of HIV infection, MPA detection was more frequent among women who acquired HIV (adjusted odds ratio = 2.75, 95% confidence interval 1.22-6.19). In this subset, the increase in HIV risk was only among samples with MPA detected at a low level of 0.02-0.50 ng/ml: 36.7% of cases and 9.4% of controls, adjusted odds ratio = 6.03, 95% confidence interval 2.50-14.54.

CONCLUSION

Detection of MPA at low levels close to the estimated time of HIV acquisition was significantly more frequent among women who acquired HIV. Studies are needed that explore biological mechanisms elicited by any MPA level and HIV risk.

Use of contraceptive depot medroxyprogesterone acetate is associated with impaired cervicovaginal mucosal integrity

BACKGROUND

Injectable depot medroxyprogesterone acetate (DMPA) is one of the most popular contraception methods in areas of high HIV seroprevalence. Evidence is accumulating that use of DMPA might be associated with an increased risk of HIV-1 acquisition by women; however, mechanisms of this association are not completely understood. The goal of this study was to gain insight into mechanisms underlying the possible link between use of DMPA and risk of HIV-1 acquisition, exploring transcription profiling of ectocervical tissues.

METHODS

Healthy women received either DMPA (n = 31) or combined oral contraceptive (COC), which has not been linked to an increased risk of HIV acquisition (n = 32). We conducted a comparative microarray-based whole-genome transcriptome profiling of human ectocervical tissues before and after 6 weeks of hormonal contraception use.

RESULTS

The analysis identified that expression of 235 and 76 genes was significantly altered after DMPA and COC use, respectively. The most striking effect of DMPA, but not COC, was significantly altered expression (mostly downregulation) of many genes strategically involved in the maintenance of mucosal barrier function; the alterations, as indicated by Ingenuity Pathway Analysis (IPA), were most likely due to the DMPA-induced estrogen deficiency. Furthermore, IPA predicted that transcriptome alterations related to ectocervical immune responses were in general compatible with an immunosuppressive effect of DMPA, but, in some women, also with an inflammatory-like response.

CONCLUSION

Our results suggest that impairment of cervicovaginal mucosal integrity in response to DMPA administration is an important mechanism contributing to the potential increased risk of HIV-1 acquisition in DMPA users.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01421368.

FUNDING

This study was supported by the United States Agency for International Development (USAID) under Cooperative Agreement GPO-A-00-08-00005-00.

Hormonal Contraception and HIV-1 Acquisition: Biological Mechanisms

Access to effective affordable contraception is critical for individual and public health. A wide range of hormonal contraceptives (HCs), which differ in composition, concentration of the progestin component, frequency of dosage, and method of administration, is currently available globally. However, the options are rather limited in settings with restricted economic resources that frequently overlap with areas of high HIV-1 prevalence. The predominant contraceptive used in sub-Saharan Africa is the progestin-only three-monthly injectable depot medroxyprogesterone acetate. Determination of whether HCs affect HIV-1 acquisition has been hampered by behavioral differences potentially confounding clinical observational data. Meta-analysis of these studies shows a significant association between depot medroxyprogesterone acetate use and increased risk of HIV-1 acquisition, raising important concerns. No association was found for combined oral contraceptives containing levonorgestrel, nor for the two-monthly injectable contraceptive norethisterone enanthate, although data for norethisterone enanthate are limited. Susceptibility to HIV-1 and other sexually transmitted infections may, however, be dependent on the type of progestin present in the formulation. Several underlying biological mechanisms that may mediate the effect of HCs on HIV-1 and other sexually transmitted infection acquisition have been identified in clinical, animal, and ex vivo studies. A substantial gap exists in the translation of basic research into clinical practice and public health policy. To bridge this gap, we review the current knowledge of underlying mechanisms and biological effects of commonly used progestins. The review sheds light on issues critical for an informed choice of progestins for the identification of safe, effective, acceptable, and affordable contraceptive methods.

The role of lactic acid production by probiotic Lactobacillus species in vaginal health

Vaginal eubiosis is characterised by beneficial lactobacillus-dominated microbiota. In contrast, vaginal dysbiosis (e.g. bacterial vaginosis, BV), characterised by an overgrowth of multiple anaerobes, is associated with an increased risk of adverse urogenital and reproductive health outcomes. A major distinguishing feature between the vaginal environment in states of eubiosis and dysbiosis is a high concentration of lactic acid, produced by lactobacilli, that acidifies the vagina in eubiosis versus a sharp drop in lactic acid and an increase in pH in dysbiosis. Here we review the antimicrobial, antiviral and immunomodulatory properties of lactic acid and the use of lactic acid and lactobacilli probiotics in preventing or treating BV.

An updated systematic review of epidemiological evidence on hormonal contraceptive methods and HIV acquisition in women

Objective and design:

Some studies suggest that specific hormonal contraceptive methods [particularly depot medroxyprogesterone acetate (DMPA)] may increase women's HIV acquisition risk. We updated a systematic review to incorporate recent epidemiological data.

Methods:

We searched for articles published between 15 January 2014 and 15 January 2016 and hand-searched reference lists. We identified longitudinal studies comparing users of a specific hormonal contraceptive method against either nonusers of hormonal contraception or users of another specific hormonal contraceptive method. We added newly identified studies to those in the previous review, assessed study quality, created forest plots to display results, and conducted a meta-analysis for data on DMPA versus non-use of hormonal contraception.

Results:

We identified 10 new reports of which five were considered ‘unlikely to inform the primary question’. We focus on the other five reports, along with nine from the previous review, which were considered ‘informative but with important limitations’. The preponderance of data for oral contraceptive pills, injectable norethisterone enanthate, and levonorgestrel implants do not suggest an association with HIV acquisition, though data for implants are limited. The new, higher quality studies on DMPA (or nondisaggregated injectables), which had mixed results in terms of statistical significance, had hazard ratios between 1.2 and 1.7, consistent with our meta-analytic estimate for all higher quality studies of hazard ratio 1.4.

Conclusion:

Although confounding in these observational data cannot be excluded, new information increases concerns about DMPA and HIV acquisition risk in women. If the association is causal, the magnitude of effect is likely hazard ratio 1.5 or less. Data for other hormonal contraceptive methods, including norethisterone enanthate, are largely reassuring.