Hormonal contraception and incident HIV-1 infection: new insight and continuing challenges

Pharmaceuticals and modern statecraft in South Africa: the cases of opium, thalidomide and contraception

This article provides a history of three pharmaceuticals in the making of modern South Africa. Borrowing and adapting Arthur Daemmrich's term 'pharmacopolitics', we examine how forms of pharmaceutical governance became integral to the creation and institutional practices of this state. Through case studies of three medicaments: opium (late 19th to early 20th century), thalidomide (late 1950s to early 1960s) and contraception (1970s to 2010s), we explore the intertwining of pharmaceutical regulation, provision and consumption. Our focus is on the modernist imperative towards the rationalisation of pharmaceutical oversight, as an extension of the state's bureaucratic and ideological objectives, and, importantly, as its obligation. We also explore adaptive and illicit uses of medicines, both by purveyors of pharmaceuticals, and among consumers. The historical sweep of our study allows for an analysis of continuities and changes in pharmaceutical governance. The focus on South Africa highlights how the concept of pharmacopolitics can usefully be extended to transnational-as well as local-medical histories. Through the diversity of our sources, and the breadth of their chronology, we aim to historicise modern pharmaceutical practices in South Africa, from the late colonial era to the Post-Apartheid present.

Contraceptive methods and risk of HIV acquisition or female-to-male transmission

Effective family planning with modern contraception is an important intervention to prevent unintended pregnancies which also provides personal, familial, and societal benefits. Contraception is also the most cost-effective strategy to reduce the burden of mother-to-child HIV transmission for women living with HIV who wish to prevent pregnancy. There are concerns, however, that certain contraceptive methods, in particular the injectable contraceptive depot medroxyprogesterone acetate (DMPA), may increase a woman's risk of acquiring HIV or transmitting it to uninfected males. These concerns, if confirmed, could potentially have large public health implications. This paper briefly reviews the literature on use of contraception among women living with HIV or at high risk of HIV infection. The Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) recommendations place no restrictions on the use of hormonal contraceptive methods by women with or at high risk of HIV infection, although a clarification recommends that, given uncertainty in the current literature, women at high risk of HIV who choose progestogen-only injectable contraceptives should be informed that it may or may not increase their risk of HIV acquisition and should also be informed about and have access to HIV preventive measures, including male or female condoms.

Hormonal contraception and HIV-1 infection: medroxyprogesterone acetate suppresses innate and adaptive immune mechanisms

Recent observational studies indicate an association between the use of hormonal contraceptives and acquisition and transmission of HIV-1. The biological and immunological mechanisms underlying the observed association are unknown. Depot medroxyprogesterone acetate (DMPA) is a progestin-only injectable contraceptive that is commonly used in regions with high HIV-1 prevalence. Here we show that medroxyprogesterone acetate (MPA) suppresses the production of key regulators of cellular and humoral immunity involved in orchestrating the immune response to invading pathogens. MPA inhibited the production of interferon (IFN)-γ, IL-2, IL-4, IL-6, IL-12, TNFα, macrophage inflammatory protein-1α (MIP-1α), and other cytokines and chemokines by peripheral blood cells and activated T cells and reduced the production of IFNα and TNFα by plasmacytoid dendritic cells in response to Toll-like receptor-7, -8, and -9 ligands. Women using DMPA displayed lower levels of IFNα in plasma and genital secretions compared with controls with no hormonal contraception. In addition, MPA prevented the down-regulation of HIV-1 coreceptors CXCR4 and CCR5 on the surface of T cells after activation and increased HIV-1 replication in activated peripheral blood mononuclear cell cultures. The presented results suggest that MPA suppresses both innate and adaptive arms of the immune system resulting in a reduction of host resistance to invading pathogens.

Population-level impact of hormonal contraception on incidence of HIV infection and pregnancy in women in Durban, South Africa

OBJECTIVE

To estimate the potential impact of using hormonal contraceptives on rates of infection with human immunodeficiency virus type 1 (HIV-1) and pregnancy by theoretically removing the use of hormonal contraceptives from a study population.

METHODS

A prospective cohort study included 3704 HIV-negative women who were enrolled in two biomedical trials that tested two vaginal microbicides (PRO 2000 and Carraguard®) for the prevention of HIV-1 in Durban, South Africa, in 2004-2009. Cox proportional hazards regression models along with partial population attributable risks (PARs) and their 95% confidence intervals (CIs) were calculated to assess the relative population-level impact of the use of hormonal contraceptives on HIV-1 seroconversion rates and on pregnancy rates.

FINDINGS

Women who reported using hormonal contraceptives at enrolment in the trial had a higher risk of HIV-1 seroconversion (adjusted hazards ratio: 1.24; 95% CI: 0.97-1.58) than women who reported using other types of contraceptives at enrolment. At the population level, the use of hormonal contraceptives (pills or injectables) at baseline and during study follow-up accounted for approximately 20% (95% CI: 16-22) of HIV-1 seroconversions. However, the partial PAR indicated a relative impact of 12% (95% CI: 9.0-15.7). On the other hand, 72% (95% CI: 66-77) of the pregnancies could have been avoided if all women had used hormonal contraceptives.

CONCLUSION

Women using hormonal contraceptives need comprehensive counselling on simultaneous prevention of HIV-1 infection.

The effects of injectable hormonal contraceptives on HIV seroconversion and on sexually transmitted infections

OBJECTIVES

To investigate the association between hormonal contraceptives and risk of HIV-1 seroconversion and prevalence of other sexually transmitted infections.

DESIGN

Prospective cohort.

METHODS

The study population was 2,236 HIV-negative women who were screened in a biomedical intervention trial in Durban, South Africa. The association between the use of hormonal contraceptives and risk of HIV-1 seroconversion was modeled using Cox proportional hazards regression analysis. Prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae infections were assessed using logistic regression models.

RESULTS

Hormonal injectables were the most common method of contraceptives (46.47%) followed by condom use (28.04%). Overall, compared with women who reported using condoms or other methods as their preferred form of contraceptive, those who reported using hormonal contraceptives (injectables and oral pills) were less likely to use condoms in their last sexual act. Using hormonal injectables during the study was significantly associated with increased risk for HIV-1 infection [adjusted hazard ratio 1.72, 95% confidence interval (CI) 1.19-2.49, P = 0.005]; hormonal injectables were also significantly associated with higher prevalent of C. trachomatis infections (adjusted odds ratio 2.46, 95% CI 1.52-3.97, P < 0.001).

CONCLUSION

Hormonal injectables are highly effective and well tolerated family planning methods and have played an important role in reducing unplanned pregnancies and maternal and infant mortality. However, they do not protect against HIV-1 and other sexually transmitted infections. This study reinforces the importance of comprehensive contraceptive counseling to women about the importance of dual protection, such as male condoms and hormonal contraceptives use.

HIV infection in the female genital tract: discrete influence of the local mucosal microenvironment

Women acquire HIV infections predominantly at the genital mucosa through heterosexual transmission. Therefore, the immune milieu at female genital surfaces is a critical determinant of HIV susceptibility. In this review, we recapitulate the evidence suggesting that several distinctive innate immune mechanisms in the female genital tract (FGT) serve to significantly deter or facilitate HIV-1 infection. Epithelial cells lining the FGT play a key role in forming a primary barrier to HIV entry. These cells express Toll-like receptors and other receptors that recognize and respond directly to pathogens, including HIV-1. In addition, innate biological factors produced by epithelial and other cells in the FGT have anti-HIV activity. Female sex hormones, co-infection with other pathogens and components in semen may also exacerbate or down-modulate HIV transmission. A combination of innate and adaptive immune factors and their interactions with the local microenvironment determine the outcome of HIV transmission. Improving our understanding of the female genital microenvironment will be useful in developing treatments that augment and sustain protective immune responses in the genital mucosa, such as microbicides and vaccines, and will provide greater insight into viral pathogenesis in the FGT.

Depo-provera treatment does not abrogate protection from intravenous SIV challenge in female macaques immunized with an attenuated AIDS virus

BACKGROUND

In a previous study, progesterone treatment of female monkeys immunized with live, attenuated SHIV89.6 abrogated the generally consistent protection from vaginal simian immunodeficiency virus (SIV) challenge. The mechanisms responsible for the loss of protection remain to be defined. The objective of the present study was to determine whether Depo-Provera administration alters protection from intravenous SIV challenge in SHIV-immunized female macaques.

METHODS AND FINDINGS

Two groups of female macaques were immunized with attenuated SHIV89.6 and then challenged intravenously with SIVmac239. Four weeks before challenge, one animal group was treated with Depo-Provera, a commonly used injectable contraceptive progestin. As expected, SHIV-immunized monkeys had significantly lower peak and set-point plasma viral RNA levels compared to naïve controls, but in contrast to previously published findings with vaginal SIV challenge, the Depo-Provera SHIV-immunized animals controlled SIV replication to a similar, or even slightly greater, degree than did the untreated SHIV-immunized animals. Control of viral replication from week 4 to week 20 after challenge was more consistent in the progesterone-treated, SHIV-immunized animals than in untreated, SHIV-immunized animals. Although levels of interferon-gamma production were similar, the SIV-specific CD8(+) T cells of progesterone-treated animals expressed more functions than the anti-viral CD8(+) T cells from untreated animals.

CONCLUSIONS

Depo-Provera did not diminish the control of viral replication after intravenous SIV challenge in female macaques immunized with a live-attenuated lentivirus. This result contrasts with the previously reported effect of Depo-Provera(R) on protection from vaginal SIV challenge and strongly implies that the decreased protection from vaginal challenge is due to effects of progesterone on the genital tract rather than to systemic effects. Further, these results demonstrate that the effects of hormonal contraceptives on vaccine efficacy need to be considered in the context of testing and use of an AIDS vaccine.

Sex steroid hormones, hormonal contraception, and the immunobiology of human immunodeficiency virus-1 infection

Worldwide, an increasing number of women use oral or injectable hormonal contraceptives. However, inadequate information is available to aid women and health care professionals in weighing the potential risks of hormonal contraceptive use in individuals living with HIV-1 or at high risk of infection. Numerous epidemiological studies and challenge studies in a rhesus macaque model suggest that progesterone-based contraceptives increase the risk of HIV-1 infection in humans and simian immunodeficiency virus (SIV) infection in macaques, accelerate disease progression, and increase viral shedding in the genital tract. However, because several other studies in humans have not observed any effect of exogenously administered progesterone on HIV-1 acquisition and disease progression, the issue continues to be a topic of intense research and ongoing discussion. In contrast to progesterone, systemic or intravaginal treatment with estrogen efficiently protects female rhesus macaques against the transmission of SIV, likely by enhancing the natural protective properties of the lower genital tract mucosal tissue. Although the molecular and cellular mechanisms underlying the effect of sex steroid hormones on HIV-1 and SIV acquisition and disease progression are not well understood, progesterone and estrogen are known to regulate a number of immune mechanisms that may exert an effect on retroviral infection. This review summarizes current knowledge of the effects of various types of sex steroid hormones on immune processes involved in the biology of HIV-1 infection.

Contraception and HIV infection in women

BACKGROUND

More than 15 million women, many of reproductive age, were infected with human immunodeficiency virus (HIV) at the end of 2007. As the HIV epidemic evolves, heterosexual intercourse is increasingly risky: the risk of infection in exposed young women is 4- to 7-fold higher than in young men and nearly half a million newborns annually have HIV. This review aims to show the effect of contraceptive choices on risk of HIV and on the course of disease in women with HIV.

METHODS

Relevant citations were selected by agreement between the authors after a search of MEDLINE using the terms HIV/AIDS and contraception.

RESULTS

Risk of transmission of HIV varies from 1 in 200 to 1 in 10 000 coital incidents, depending in part on the integrity of the vaginal epithelium. Consistent use of male condoms has been proven to reduce horizontal transmission of HIV by 80% among HIV-serodiscordant couples. Hormonal contraception may increase the risk of HIV acquisition in high-risk women such as commercial sex workers, but not in women at low risk of HIV. While hormonal contraception did not affect progression of disease in two cohort studies involving 370 women, in a randomized trial among women not receiving antiretroviral medication, clinical disease accelerated in the oral contraception group (13.2/100 woman-years) compared with the copper intrauterine devices group (8.6/100 woman-years; hazard ratio, 1.5; 95% confidence interval, 1.04-2.1). Hormonal contraception does not interfere with antiviral drug effectiveness.

CONCLUSIONS

All the available reversible contraceptive methods can generally be used by women at risk of HIV infection and by HIV-infected women. Further studies are needed to investigate the safety and efficiency of hormonal contraception in women living with HIV/AIDS.

Natural history and risk factors associated with early and established HIV type 1 infection among reproductive-age women in Malawi

BACKGROUND

Data evaluating the biological events and determinants of early human immunodeficiency virus type 1 (HIV-1) infection are limited in sub-Saharan Africa. We examined plasma viral levels and trends during early and established HIV-1 infection among reproductive-age women who participated in a randomized trial to treat genital tract infection in Malawi. We also assessed the association of injectable hormonal contraceptive use with HIV-1 infection.

METHODS

We studied 3 groups of women who were infected or uninfected with HIV-1: seroconverters, seroprevalent women, and seronegative women. Questionnaires and blood samples were collected at baseline and every 3 months for 1 year. The virus set point in seroconverters and levels and trends of viral load over time were determined. The associations of injectable hormonal contraceptive use with HIV-1 infection and viral load were assessed using conditional logistic regression and mixed-effect models, respectively.

RESULTS

In the original clinical trial, 844 women infected with HIV-1 and 842 women not infected with HIV-1 were enrolled. Of 31 women who experienced seroconversion during 12 months, 27 were matched with 54 seroprevalent and 54 seronegative women. The estimated median plasma virus set point was 4.45 log(10) copies/mL (interquartile range, 4.32-5.14 log(10) copies/mL). Injectable hormonal contraceptive use was significantly associated with HIV-1 seroconversion (adjusted odds ratio, 10.42; P = .03) but not with established HIV-1 infection. Among the seroconverters, a statistically significant interaction was found between the linear association of viral load and time of injectable hormonal contraceptive use (regression coefficient, -0.14; P = .02).

CONCLUSION

Knowledge of virus set point and trends of viral load in HIV-1 seroincident and seroprevalent asymptomatic women could assist in antiretroviral treatment management.

Hormonal contraceptive use, herpes simplex virus infection, and risk of HIV-1 acquisition among Kenyan women

BACKGROUND

Studies of the effect of hormonal contraceptive use on the risk of HIV-1 acquisition have generated conflicting results. A recent study from Uganda and Zimbabwe found that women using hormonal contraception were at increased risk for HIV-1 if they were seronegative for herpes simplex virus type 2 (HSV-2), but not if they were HSV-2 seropositive.

OBJECTIVE

To explore the effect of HSV-2 infection on the relationship between hormonal contraception and HIV-1 in a high-risk population. Hormonal contraception has previously been associated with increased HIV-1 risk in this population.

METHODS

Data were from a prospective cohort study of 1206 HIV-1 seronegative sex workers from Mombasa, Kenya who were followed monthly. Multivariate Cox proportional hazards analyses were used to adjust for demographic and behavioral measures and incident sexually transmitted diseases.

RESULTS

: Two hundred and thirty-three women acquired HIV-1 (8.7/100 person-years). HSV-2 prevalence (81%) and incidence (25.4/100 person-years) were high. In multivariate analysis, including adjustment for HSV-2, HIV-1 acquisition was associated with use of oral contraceptive pills [adjusted hazard ratio (HR), 1.46; 95% confidence interval (CI), 1.00-2.13] and depot medroxyprogesterone acetate (adjusted HR, 1.73; 95% CI, 1.28-2.34). The effect of contraception on HIV-1 susceptibility did not differ significantly between HSV-2 seronegative versus seropositive women. HSV-2 infection was associated with elevated HIV-1 risk (adjusted HR, 3.58; 95% CI, 1.64-7.82).

CONCLUSIONS

In this group of high-risk African women, hormonal contraception and HSV-2 infection were both associated with increased risk for HIV-1 acquisition. HIV-1 risk associated with hormonal contraceptive use was not related to HSV-2 serostatus.

Reproductive Choice for Women and Men Living with HIV: Contraception, Abortion and Fertility

From a policy and programmatic point of view, this paper reviews the literature on the fertility-related needs of women and men living with HIV and how the entry points represented by family planning, sexually transmitted infection and HIV-related services can ensure access to contraception, abortion and fertility services for women and men living with HIV. Most contraceptive methods are safe and effective for HIV positive women and men. The existing range of contraceptive options should be available to people living with HIV, along with more information about and access to emergency contraception. Potential drug interaction must be considered between hormonal contraception and treatment for tuberculosis and certain antiretroviral drugs. Couples living with HIV who wish to use a permanent contraceptive method should have access to female sterilisation and vasectomy in an informed manner, free of coercion. How to promote condoms and dual protection and how to make them acceptable in long term-relationships remains a challenge. Both surgical and medical abortion are safe for women living with HIV. To reduce risk of vertical transmission of HIV and in cases of infertility, people with HIV should have access to sperm washing and other assisted conception methods, if these are available. Simple and cost-effective procedures to reduce risk of vertical transmission should be part of counselling for women and men living with HIV who intend to have children. Support for the reproductive rights of people with HIV is a priority. More operations research on best practices is needed.