Concomitant contraceptive implant and efavirenz use in women living with HIV: perspectives on current evidence and policy implications for family planning and HIV treatment guidelines

Drug-drug interactions between antiretrovirals and hormonal contraception: An updated systematic review

OBJECTIVE

To summarize and update information regarding drug-drug interactions (DDIs) between antiretrovirals (ARVs) and hormonal contraceptives (HCs).

STUDY DESIGN

Systematic review.

RESULTS

We included 49 articles, with clinical, ARV, or HC PK outcomes reported by 39, 25, and 30 articles, respectively, with some articles reporting outcomes in two or more categories. Fifteen of 18 articles assessing DDIs between efavirenz and progestin implants, emergency contraception, or combined hormonal intravaginal rings found higher pregnancy rates, luteal progesterone levels suggesting ovulation, or reduced progestin PK values. Five studies documented that CYP2B6 single nucleotide polymorphisms exacerbated this DDI. One cohort detected doubled bone density loss with concomitant depot medroxyprogesterone acetate (DMPA) and tenofovir disoproxil fumarate (TDF)-containing ART use versus TDF alone. No other studies described DDIs impacting clinical outcomes. Few adverse events were attributed to ARV-HC use with none exceeding Grade 2. Evidence quality was generally moderate, with dis-similar treatment and control groups, identifying and controlling for confounding, and minimizing attrition bias in the study design being the most frequent limitations.

CONCLUSION

TDF-DMPA DDIs warrant longer-term study on bone health and consideration of alternate combinations. For efavirenz-based ART, client counseling on relative risks, including both potential increase in pregnancy rate with concomitant efavirenz and implant use and lower pregnancy rates compared to other HCs even with concomitant efavirenz use, should continue to allow users comprehensive method choice.

IMPLICATIONS

Most ARVs and HCs may be used safely and effectively together. Efavirenz-based ART requires careful counseling and data for possible interactions between HCs and new ARV classes are anticipated.

Experiences of women on the use of Implanon NXT in Gauteng province, South Africa: A qualitative study

Background

Maternal-related illnesses and pregnancy-related deaths could be averted using contraceptives, particularly long-acting methods because they improve overall access to family planning because of their benefits, such as fewer visits to the healthcare facility, higher effectiveness and value for money. The introduction of Implanon NXT in the South African health system raised great concern about the number of women who returned to healthcare facilities for its early removal within a few months of insertion.

Aim

This article focussed on exploring the experiences of women regarding early removal of Implanon NXT insertion.

Setting

The study was conducted in four selected clinics in Region E sub-district, city of Johannesburg.

Methods

A qualitative exploratory approach was followed using semi-structured individual interviews to collect data. Data were analysed using the content analysis method.

Results

The most cited reasons for its discontinuity were that women experienced unpleasant side effects such as amenorrhoea, excessive bleeding and headaches, whilst other women found it to be reliable and convenient.

Conclusion

Contraceptive methods empower women to take control of their lives and to decide on the right time for them to have children. It is, therefore, important to equip women with relevant information about the contraceptive methods so that they can make informed decisions and choices.

Contribution

The study calls for health promoters to periodically conduct information sessions with women as guided by the National Contraception Policy Guidelines to ensure up-to-date practice.

Key programmatic and policy considerations for introducing multipurpose prevention (MPT) methods: reflections from healthcare providers and key stakeholders in South Africa

Introduction

Multipurpose prevention technologies (MPTs) simultaneously prevent HIV, other sexually transmitted infections, and/or unintended pregnancy. Key gatekeepers, [healthcare providers (HCPs) and key stakeholders] require proactive engagement before product implementation. This manuscript identifies HCP demand creation strategies, key stakeholder considerations for the adoption of MPTs in South Africa.

Methods

Formative research was conducted in three districts in three South African provinces (July to November 2022). Nurses initiating oral PrEP at facility and mobile study sites participated in 4-hour participatory workshops, exploring HIV prevention, including MPTs, demand creation strategies, and preferred MPTs training packages. Activities were observed, transcribed, and thematically analysed. Five online in-depth interviews (IDIs) with Key informants (KIs) (National/district programme implementers and technical leads) and one in person, exploring key programmatic and policy considerations for MPT adoption. IDIs were approximately 40 min long, audio recorded, transcribed, and thematically analysed.

Results

Twenty-one Professional Nurses completed workshops: 19 female. Six IDIs were conducted with 4 Facility Managers, 1 NDoH representative and 1 DoH Provincial Deputy Director. All participants were females, aged 30-60+ years with >10 years' in SRH/HIV policy/advocacy/research. Community conversations and information at the clinic were the best MPT demand creation methods among HCPs. KIs identified five considerations for future MPT implementation: HCP training; demand creation and messaging; existing PrEP policy amendments; preparing users for additional choice; and sustaining MPT provision.

Conclusion

Contraceptive implant and oral PrEP implementation lessons learned should be proactively considered when preparing for MPT introduction. HCP training and demand creation are of particular importance before MPT introduction.

Contraception and Abortion Care for People Living With HIV: A Clinical Guide for Reproductive Health Practitioners

People capable of pregnancy are disproportionately affected by HIV. Family planning needs and services are often unmet in this population, and clinical care guidelines regarding contraceptive options and abortion care are not well elucidated. Individuals living with HIV often face unique barriers in accessing contraception and abortion services due to internalized stigma, medically complex care (eg, drug-drug interactions, adverse effects of antiretroviral therapy), and distrust of health care providers. There is also a lack of clarity among reproductive health, primary, and infectious disease care providers on best-practice contraceptive counseling and contraceptive care for individuals living with HIV, given limited opportunities to enhance expertise in reproductive infectious disease. In this review, we summarize existing and updated evidence and clinical considerations regarding contraceptive counseling and abortion care in this population.

Unintended pregnancies among HIV-positive women in sub-Saharan Africa: a scoping review protocol

BACKGROUND

Unintended pregnancies pose a severe threat to the well-being of HIV-positive women and their unborn children. Factors contributing to the high incidence of unintended pregnancies include contraceptive failure, low uptake of contraceptives, and misuse of contraceptives. Despite various contraceptive options, an increased incidence of unintended pregnancies is rampant among HIV-positive women in the region of sub-Saharan Africa. This study seeks to present evidence of unintended pregnancies among women living with HIV in sub-Saharan Africa, including those using contraceptives.

METHOD

This study entails a scoping review to survey and interrogate the literature to provide evidence for the incidence of unintended pregnancies among HIV-positive women in sub-Saharan Africa. A proposed framework by Arksey and O'Malley will guide this scoping review. Peer-reviewed articles which address the research questions will constitute the main search. Electronic databases such as EBSCOhost, Cochrane Library, World of Science, World Health Organization (WHO) library databases, Science Direct, Google Scholar PubMed, and gray literature search will be involved. Reference list from studies included will also be searched. The investigation of articles will be done employing keywords from the studies included. The inclusion and exclusion criteria will guide two separate reviewers with the screening of abstracts and full papers. To summarize the findings from this review, thematic content analysis will be done using NVivo version 11.

DISCUSSION

We expect that this review will add to the current body of knowledge on the incidence of unintended pregnancies among HIV-positive women, identify gaps for further future research, and show evidence that may contribute to strengthening the health system's regulations, guidelines, and policies that may help prevent unintended pregnancies among HIV-positive women.

SYSTEMATIC REVIEW REGISTRATION

10.17605/OSF.IO/EY3R5.

Contraceptive Use and Missed Opportunities for Family Planning Discussions in Women Living with Human Immunodeficiency Virus at an HIV Clinic

The objective of this study was to examine contraception use and family planning discussions (FPD) in female people living with HIV (PLWH). A retrospective cohort study was conducted. Female PLWH were included if they were 18-44 years and received care in 2019 at an HIV clinic. 74 patients met inclusion; mean age was 35 years, 53% were white. All patients were prescribed antiretroviral therapy. 48.6% of patients had documented FPD. 64.9% of patients were using contraception; sterilization was most common (41.7%). Only five patients had a contraindication to hormonal contraception. No differences in contraception use were observed based on age, race, HIV viral load, number of visits, or past pregnancies. However, patients with documented FPD were more likely to use contraception (OR 4.55; 95% CI 1.35-15.29). Routine FPD and contraception use in female PLWH were low. Rates of sterilization were high in female PLWH. Providing quality family planning services is critical to increase contraception use and selection of the most appropriate contraception form.

Contraceptive implant use duration is not associated with breakthrough pregnancy among women living with HIV and using efavirenz: a retrospective, longitudinal analysis

Introduction

Contraceptive implants containing etonogestrel and levonorgestrel have emerged as popular contraceptive options among women in areas of high HIV burden in sub‐Saharan Africa. However, recent pharmacokinetic data have shown drug–drug interactions between implants and efavirenz‐containing antiretroviral therapy (ART), reducing the effectiveness of the implants. Here, we evaluated pregnancy incidence in 6‐month intervals following implant initiation among women using efavirenz and contraceptive implants to assess whether the risk of breakthrough pregnancy is higher after specific periods of implant use.

Methods

We used data from a retrospective longitudinal analysis of women living with HIV ages 18–45 years in western Kenya who attended HIV‐care facilities between 2011 and 2015. We used Cox proportional hazard models to compute hazard ratios (HRs) for breakthrough pregnancy by implant type and ART regimen. Depending on the model, we adjusted for socio‐demographic and clinical factors, programme, site and interaction between calendar time and ART regimen. We utilized inverse probability weights (IPWs) to account for three sampling phases (electronic medical record [EMR], chart review and phone interview) and calculated overall parameter estimates.

Results

Women contributed 14,768 woman‐years from the largest sampling phase (EMR). The median age was 31 years. Women used etonogestrel implants for 26–69% of the time and levonorgestrel implants for 7–31% of the time, depending on the sampling phase. Women used efavirenz, nevirapine or no ART for 27–33%, 40–46% and 15–26% of follow‐ups, respectively. When combining sampling phases, there was little evidence to suggest that the relative hazard of pregnancy among efavirenz‐containing ART users relative to nevirapine‐containing ART changed with length of time on implants: IPW‐adjusted HR of 3.1 (CI: [1.5; 6.4]) at 12 months, 3.4 (CI: [1.8; 6.3]) at 24 months, 3.8 (CI: [1.9; 7.7]) at 36 months and 4.2 (CI: [1.6; 11.1]) at 48 months (interaction p‐value = 0.88). Similarly, no significant change in HRs over time was found when comparing women not using ART to nevirapine‐containing ART users (interaction p‐value = 0.49).

Conclusions

We did not find evidence to suggest implants being more fallible from drug–drug interactions with efavirenz at later time intervals of implant use. Thus, we would not recommend shortening the duration of implant use or replacing implants sooner when concomitantly used with efavirenz.

Implants for HIV prevention in young women: Provider perceptions and lessons learned from contraceptive implant provision

Preventing new HIV infections, especially amongst young women, is key to ending the HIV epidemic especially in sub-Saharan Africa. Potent antiretroviral (ARV) drugs used as pre-exposure prophylaxis (PrEP) are currently being formulated as long-acting implantable devices, or nanosuspension injectables that release drug at a sustained rate providing protection from acquiring HIV. PrEP as implants (PrEP Implants) offers an innovative and novel approach, expanding the HIV prevention toolbox. Feedback from providers and future users in the early clinical product development stages may identify modifiable characteristics which can improve acceptability and uptake of new technologies. Healthcare workers (HCWs) perspectives and lessons learned during the rollout of contraceptive implants will allow us to understand what factors may impact the roll-out of PrEP implants. We conducted eighteen interviews with HCWs (9 Nurses and 9 Community Healthcare Workers) in rural KwaZulu-Natal, South Africa. HCWs listed the long-acting nature of the contraceptive implant as a key benefit, helping to overcome healthcare system barriers like heavy workloads and understaffing. However, challenges like side effects, migration of the implant, stakeholder buy-in and inconsistent training on insertion and removal hampered the roll-out of the contraceptive implant. For PrEP implants, HCWs preferred long-acting products that were palpable and biodegradable. Our findings highlighted that the characteristics of PrEP implants that are perceived to be beneficial by HCWs may not align with that of potential users, potentially impacting the acceptability and uptake of PrEP implants. Further our data highlight the need for sustained and multi-pronged approaches to training HCWs and introducing new health technologies into communities. Finding a balance between the needs of HCWs that accommodate their heavy workloads, limited resources at points of delivery of care and the needs and preferences of potential users need to be carefully considered in the development of PrEP implants.

Contraceptive trajectories postpartum: A longitudinal qualitative study of women living with HIV in Cape Town, South Africa

BACKGROUND

Supporting the ability of women living with HIV (WLWH) to avoid unintended pregnancy during the postpartum period decreases the number of new pediatric HIV infections, reduces pregnancy-related morbidity and mortality, and is a cost-effective strategy for the elimination of mother-to-child transmission. However, little is currently known about the contraceptive intentions and experiences of reinitiating family planning use among mothers living with HIV as they transition from pregnancy into postpartum.

STUDY OBJECTIVES

To (1) understand the contraceptive trajectories of women living with HIV during pregnancy and postpartum in Cape Town, South Africa, and (2) identify factors shaping differing contraceptive trajectories during the postpartum period.

METHODS

Thirty pregnant WLWH were interviewed during their eighth month of pregnancy and completed follow-up interviews at 6-8 weeks and 9-12 months postpartum (n = 81 total interviews). Interview topics included postpartum contraception intentions, contraceptive use, and experiences accessing family planning services. Trajectory analysis of contraceptive intentions was applied after initial thematic coding.

RESULTS

While nearly half of women interviewed during pregnancy expressed an intention to utilize a non-injectable contraceptive option after childbirth (e.g. implant, IUD, sterilization, oral contraceptive pills), all women interviewed at one year postpartum had received at least one injection. Three main contraceptive trajectories were identified. (1) realization of contraceptive intentions postpartum; (2) unrealized contraceptive intentions postpartum; and (3) change in contraceptive intention over time. Provider influence, coordination of services, and low contraceptive inventory were identified as potential factors shaping the contraceptive trajectories of participants enrolled in the study.

CONCLUSION

Disparities between contraceptive method intentions articulated by WLWH during pregnancy and methods attained postpartum suggest that significant barriers remain for women who are unsatisfied with injectable contraception. Failing to provide postpartum mothers living with HIV their intended family planning method undermines efforts to prevent unintended pregnancy, a key pillar of elimination of mother-to-child transmission.

Pregnancies among women living with HIV using contraceptives and antiretroviral therapy in western Kenya: a retrospective, cohort study

BACKGROUND

Preventing unintended pregnancies is paramount for women living with HIV (WLHIV). Previous studies have suggested that efavirenz-containing antiretroviral therapy (ART) reduces contraceptive effectiveness of implants, but there are uncertainties regarding the quality of the electronic medical record (EMR) data used in these prior studies.

METHODS

We conducted a retrospective, cohort study of EMR data from 2011 to 2015 among WLHIV of reproductive age accessing HIV care in public facilities in western Kenya. We validated a large subsample of records with manual chart review and telephone interviews. We estimated adjusted incidence rate ratios (aIRRs) with Poisson regression accounting for the validation sampling using inverse probability weighting and generalized raking.

RESULTS

A total of 85,324 women contributed a total of 170,845 women-years (w-y) of observation time; a subset of 5080 women had their charts reviewed, and 1285 underwent interviews. Among implant users, the aIRR of pregnancy for efavirenz- vs. nevirapine-containing ART was 1.9 (95% CI 1.6, 2.4) using EMR data only and 3.2 (95% CI 1.8, 5.7) when additionally using both chart review and interview validated data. Among efavirenz users, the aIRR of pregnancy for depomedroxyprogesterone acetate (DMPA) vs. implant use was 1.8 (95% CI 1.5, 2.1) in EMR only and 2.4 (95% CI 1.0, 6.1) using validated data.

CONCLUSION

Pregnancy rates are higher when contraceptive implants are concomitantly used with efavirenz-containing ART, though rates were similar to leading alternative contraceptive methods such as DMPA. Our data provides policymakers, program staff, and WLHIV greater confidence in guiding their decision-making around contraceptive and ART options. Our novel, 3-phase validation sampling provides an innovative tool for using routine EMR data to improve the robustness of data quality.

A Semimechanistic Pharmacokinetic Model for Depot Medroxyprogesterone Acetate and Drug-Drug Interactions With Antiretroviral and Antituberculosis Treatment

Depot medroxyprogesterone acetate is an injectable hormonal contraceptive, widely used by women of childbearing potential living with HIV and/or tuberculosis. As medroxyprogesterone acetate is a cytochrome P450 (CYP3A4) substrate, drug-drug interactions (DDIs) with antiretroviral or antituberculosis treatment may lead to subtherapeutic medroxyprogesterone acetate concentrations (< 0.1 ng/mL), resulting in contraception failure, when depot medroxyprogesterone is dosed at 12-week intervals. A pooled population pharmacokinetic analysis with 744 plasma medroxyprogesterone acetate concentrations from 138 women treated with depot medroxyprogesterone and antiretroviral/antituberculosis treatment across three clinical trials was performed. Monte Carlo simulations were performed to predict the percentage of participants with subtherapeutic medroxyprogesterone acetate concentrations and to derive alternative dosing strategies. Medroxyprogesterone acetate clearance increased by 24.7% with efavirenz coadministration. Efavirenz plus antituberculosis treatment (rifampicin + isoniazid) increased clearance by 52.4%. Conversely, lopinavir/ritonavir and nelfinavir decreased clearance (28.7% and 15.8%, respectively), but lopinavir/ritonavir also accelerated medroxyprogesterone acetate's appearance into the systemic circulation, thus shortening the terminal half-life. A higher risk of subtherapeutic medroxyprogesterone acetate concentrations at Week 12 was predicted on a typical 60-kg woman on efavirenz (4.99%) and efavirenz with antituberculosis treatment (6.08%) when compared with medroxyprogesterone acetate alone (2.91%). This risk increased in women with higher body weight. Simulations show that re-dosing every 8 to 10 weeks circumvents the risk of subtherapeutic medroxyprogesterone acetate exposure associated with these DDIs. Dosing depot medroxyprogesterone every 8 to 10 weeks should eliminate the risk of subtherapeutic medroxyprogesterone acetate exposure caused by coadministered efavirenz and/or antituberculosis treatment, thus reducing the risk of contraceptive failure.

Pharmacokinetics and Pharmacodynamics of Depot Medroxyprogesterone Acetate in African Women Receiving Treatment for Human Immunodeficiency Virus and Tuberculosis: Potential Concern for Standard Dosing Frequency

BACKGROUND

Effective contraception is critical to young women with HIV-associated tuberculosis (TB), as unintended pregnancy is associated with increased perinatal morbidity and mortality. The effects of co-administration of efavirenz and rifampicin on the pharmacokinetics of depot medroxyprogesterone acetate (DMPA) are unknown. We hypothesized that clearance of medroxyprogesterone acetate (MPA) would increase when given with rifampicin and efavirenz, thus increasing risk of ovulation.

METHODS

This pharmacokinetics (PK) study assessed DMPA among HIV/TB coinfected women on an efavirenz-based antiretroviral treatment and rifampicin-based TB treatment. Plasma MPA concentrations and progesterone were measured predose (MPA only) and 2, 4, 6, 8, 10, and 12 weeks after a single DMPA 150 mg intramuscular injection. The primary outcome measure, MPA concentration (<0.1 ng/mL) at week 12, was assessed using exact 95% Clopper-Pearson confidence intervals. MPA PK parameters were calculated using noncompartmental analysis.

RESULTS

Among 42 PK-evaluable women from 5 African countries, median age was 32 years and median CD4 was 414 cells/mm3. Five women (11.9%; 95% CI, 4.0-25.6%) had MPA <0.1 ng/mL at week 12; of these, one had MPA <0.1 ng/mL at week 10. The median clearance of MPA was 19 681 L/week compared with 12 118 L/week for historical controls. There were no adverse events related to DMPA, and progesterone concentrations were <1 ng/mL for all women for the study duration.

CONCLUSIONS

DMPA, when given with rifampicin and efavirenz, was safe. MPA clearance was higher than in women with HIV not on ART, leading to subtherapeutic concentrations of MPA in 12% of women, suggesting that more frequent dosing might be needed.

CLINICAL TRIALS REGISTRATION

NCT02412436.

Perceptions matter: Narratives of contraceptive implant robbery in Cape Town, South Africa

Uptake of contraceptive implants has declined in South Africa since their introduction in 2014, with side effects and inadequate health provider training cited as primary contributors underlying a poor community perception of implants. In this paper we explore a theme that emerged unexpectedly during analysis of our research in Cape Town that may be an additional factor in this decline: narratives of women being assaulted by robbers who physically remove the implants for smoking as drugs. Narratives were described consistently across interviews and focus groups with youth (aged 18-24 years) and in interviews with health providers, with six participants (two young people, four health providers) sharing personal experiences of robbery. While there was a range of perspectives on whether narratives are based on real experiences or are myths, there was strong consensus that narratives of implant robbery may be influencing women's decisions around implant use in Cape Town. This is a potent example of how perceptions of new products can affect uptake and offers important lessons for implementers to reflect on in planning for rollout of other health technologies.

Nexplanon failure in a woman with HIV infection in rural Ghana: A case report

Although Nexplanon is one of the most effective and most utilized long-acting reversible contraceptives in Ghana. We report a rare event of Nexplanon failure in a woman with human immunodeficiency virus (HIV) infection in rural Ghana.

Contraceptive implant failures among women using antiretroviral therapy in western Kenya: a retrospective cohort study

Background: Women living with HIV have the right to choose whether, when and how many children to have. Access to antiretroviral therapy (ART) and contraceptives, including implants, continues to increase in Kenya. Studies have reported drug-drug interactions leading to contraceptive failures among implant users on ART. This retrospective record review aimed to determine unintentional pregnancy rates among women 15-49 years of age, living with HIV and concurrently using implants and ART in western Kenya between 2011 and 2015.

Methods: We reviewed charts of women with more than three months of concurrent implant and ART use. Implant failure was defined as implant removal due to pregnancy or birth after implant placement, but prior to scheduled removal date. The incidence of contraceptive failure was calculated by woman-years at risk, assuming a constant rate.

Results: Data from 1,152 charts were abstracted, resulting in 1,190 implant and ART combinations. We identified 115 pregnancies, yielding a pregnancy incidence rate of 6.32 (5.27–7.59), with 9.26 among ETG and 4.74 among LNG implant users, respectively. Pregnancy incidence rates did not differ between EFV- and NVP-based regimens (IRR=1.00, CI: 0.71-1.43). No pregnancies were recorded among women on PI-based regimens, whereas pregnancy rates for efavirenz and nevirapine-containing regimens were similar, at 6.41 (4.70–8.73) and 6.44 (5.13–8.07), respectively. Pregnancy rates also differed significantly by implant type, with LNG implant users half as likely to experience pregnancy as ETG implant users (0.51, CI: 0.33-0.79, p>0.01).

Conclusions: Our findings highlight the implications of drug-drug interaction on women’s choices for contraception.

Perspectives on contraceptive implant use in women living with HIV in Cape Town, South Africa: a qualitative study among primary healthcare providers and stakeholders

BACKGROUND

This study explored primary healthcare provider and HIV/contraception expert stakeholder perspectives on South Africa's public sector provision of contraceptive implants to women living with HIV. We investigated the contraceptive service-impact of official advice against provision of implants to women using the HIV antiretroviral drug, efavirenz, issued by the South African National Department of Health (NDoH) in 2014.

METHODS

Qualitative data was collected in Cape Town in 2017 from primary healthcare contraceptive providers in four clinics that provide implants, as well as from other expert stakeholders selected for expertise in HIV and/or contraception. In-depth interviews and a group discussion explored South Africa's implant introduction and implant provision to women living with HIV. Data was analysed using an inductive thematic analysis approach.

RESULTS

Interviews were conducted with 10 providers and 10 stakeholders. None of the four clinics where the providers worked currently offered the implant to women living with HIV. Stakeholders confirmed that this was consistent with patterns of implant provision at primary healthcare facilities across Cape Town. Factors contributing to providers' decisions to suspend provision of the implant to women living with HIV included: inadequate initial and ongoing provider training; interpretation of NDoH communications about implant use with efavirenz; provider unwillingness to risk harming clients and concerns about professional liability; and other pressures related to provider capacity.

CONCLUSIONS

All South African women, including those living with HIV, should have access to the full range of contraceptive options for which they are medically eligible. Changing guidance should be initiated and communicated in consultation with primary-level providers and service beneficiaries. Guidance issued to providers needs to be clear and fully evidence-informed, and its correct interpretation and implementation facilitated and monitored. Guidance should be accompanied by provider training, as well as counselling messages and tools to support providers. Generalized retraining of providers in rights-based, client-centred family planning, and in particular implant provision for women with HIV, is needed. These recommendations accord with the right of women living with HIV to access the highest possible standard of sexual and reproductive healthcare, including informed contraceptive choice and access to the contraceptive implant.

Contraceptive implant failures among women using antiretroviral therapy in western Kenya: a retrospective cohort study

Background: Women living with HIV have the right to choose whether, when and how many children to have. Access to antiretroviral therapy (ART) and contraceptives, including implants, continues to increase due to a multitude of efforts. In Kenya, 4.8% of adults are living with HIV, and in 2017, 54% were receiving an efavirenz-based ART regimen. Meanwhile, 16.1% of all Kenyan married (and 10.4% of unmarried) women used implants. Studies have reported drug interactions leading to contraceptive failures among implant users on ART. This retrospective record review aimed to determine unintentional pregnancy rates among women 15-49 years of age, living with HIV and concurrently using implants and ART in western Kenya between 2011 and 2015. Methods: We reviewed charts of women with more than three months of concurrent implant and ART use. Implant failure was defined as implant removal due to pregnancy or birth after implant placement, but prior to scheduled removal date. The incidence of unintended pregnancy was calculated by woman-years at risk, assuming a constant rate. Results: Data from 1,152 charts were abstracted, resulting in 1,190 implant and ART combinations. We identified 115 pregnancies, yielding a pregnancy incidence rate of 6.32 (5.27–7.59), with 9.26 among ETG and 4.74 among LNG implant users, respectively. No pregnancies were recorded among women on non-NNRTI-based regimens, whereas pregnancy rates for efavirenz and nevirapine-containing regimens were similar, at 6.41 (4.70–8.73) and 6.44 (5.13–8.07), respectively. Conclusions: Our findings highlight the implications of drug interaction on women’s choices for contraception.