Acceptability of the Nestorone®/ethinyl estradiol contraceptive vaginal ring: development of a model; implications for introduction

Preference, adherence, and acceptability of 3 nonmedicated intravaginal rings of differing external diameters: a randomized, crossover trial

BACKGROUND

No empirical data support the 54 to 58 mm external diameter of intravaginal rings currently available and in development for contraception and other indications. Understanding how external diameter affects preference, adherence, and acceptability is critical for optimizing future product development.

OBJECTIVE

Our primary objectives were to determine which of 3 nonmedicated rings of differing external diameters was preferred and yielded the highest adherence. Secondary objectives were comparing acceptability, patterns of adherence, and safety of the 3 rings.

STUDY DESIGN

In an open-label, 3-way crossover trial, healthy, HIV-uninfected, monogamous, sexually active, nonpregnant, 18-year-old to 40-year-old cisgender women and their male partners in Atlanta, GA and the Bronx, NY were randomly assigned to the sequence of using 3 nonmedicated silicone rings (46 mm, 56 mm, and 66 mm external diameters) continuously for approximately 30 days each (90 days total; November 2021 to December 2022). We tested whether end-of-study preference for any of the 3 rings was greater than 0.33 (binomial proportion, exact test). We used mixed-effect regression models with random intercepts by participants to compare adherence (ring never out for more than 30 minutes in 24 hours) and probability of removals (including reasons for removal), expulsions, and the ring being out of the vagina all day, per ring, per day of use with the 56-mm ring as the reference group and to compare scores on a novel 19-item acceptability scale with items related to ease and experience of use and impact on sex.

RESULTS

Of 24 women, 23 completed the study (median age: 26.7 years [standard deviation: 3.78]). Most were college graduates (92%), White (63%), non-Hispanic (79%), single (79%), and nulliparous (92%). At the end of the study, 59% preferred the smallest (46 mm) ring versus 18% each for the 56-mm and 66-mm rings (P=.0045). The proportion of participants who were adherent did not differ by ring (46 mm, 78%; 56 mm, 75%; 66 mm, 59%; P=.30); however, odds of expulsion were higher for the 46-mm (odds ratio: 5.72; 95% confidence interval: 1.25-26.1) and 66-mm (odds ratio: 25.9; 95% confidence interval: 6.11-109) rings than for the 56-mm ring. The 66-mm ring also had greater odds of being out (removal or expulsion, any length of time) than the 56-mm ring (odds ratio: 6.50; 95% confidence interval: 3.46-12.2). Mean acceptability scale scores were identical (4.54/5) for the 46-mm and 56-mm (smallest and medium) rings and significantly higher than for the largest, 66-mm ring (3.94/5; P<.001).

CONCLUSION

Although the 46-mm ring was preferred by more women and had higher rates of adherence compared to the other 2 rings, the 56-mm ring was rated as equally acceptable with significantly fewer reports of expulsions/removals compared to the other 2 rings. These data confirm that the current 54 to 58 mm diameter of vaginal rings on the market and in development is acceptable and performs well. Future studies should explore the effect of other mechanical attributes, such as compressibility, on preference, adherence, and acceptability, as well as investigating ring characteristics in other populations.

A comparison of acceptability of contraceptive vaginal rings, pills, and injectables among cisgender women in Kenya and Zimbabwe: protocol for a mixed-methods study

Background

Expanding contraceptive options could better meet users' diverse needs and preferences. Annovera ® is a contraceptive vaginal ring that provides a year of pregnancy prevention while remaining under user control and allowing for regular menstrual cycles. This method may also help to reduce burdens on some health care and supply chain systems. However, knowledge gaps exist regarding initial and ongoing acceptability of contraceptive vaginal rings in African settings.

Methods

We will undertake an open-label, non-randomized, two-arm, parallel clinical acceptability study with an embedded qualitative component, based in clinics providing contraceptive services in Kenya and Zimbabwe. Women aged 18-45 interested in newly initiating or switching contraception will choose from among all available contraceptive options, including Annovera. We aim to enroll 200 participants selecting Annovera and 200 participants selecting either contraceptive injectables or pills. We will compare method uptake, continuation, and satisfaction over one year. Participants will complete questionnaires administered by study staff during two in-person visits (a screening/enrollment visit, and an end of study visit after 52 weeks of method use or at discontinuation) and four phone appointments (at 4, 12, 24, and 36 weeks of use). We will evaluate used rings for discoloration and residual drug levels. The qualitative component involve in-depth interviews with women in the clinical study, their sexual partners, and their service providers, to further examine drivers of and barriers to interest in and use of contraceptive vaginal rings.

Discussion

This study will explore acceptability of contraceptive vaginal rings in 'real-world' contraceptive service settings in two African countries. Findings will be based on actual ring use and contextualized via comparison to two other commonly available methods. As vaginal rings are being considered for multiple reproductive health indications, this work can fill key knowledge gaps and empower decision-makers with information needed to inform future investments in reproductive health.

Risk factors for and outcomes of ring expulsions with a 1-year contraceptive vaginal system

BACKGROUND

The US Food and Drug Administration-approved segesterone acetate and ethinyl estradiol ring-shaped contraceptive vaginal system, known as Annovera (Sever Pharma Solutions/QPharma, Malmö, Sweden), was inserted and removed under a woman's control for a 21 day in and 7 day out regimen for up to 13 cycles of use.

OBJECTIVE

We aimed to describe the patterns of ring expulsion over time, to identify potential predictors of expulsion, and to evaluate the impact of expulsions on method discontinuation and pregnancy risk.

STUDY DESIGN

Using data from 2064 participants who were enrolled in 2 multinational phase 3 clinical trials on the use of this contraceptive vaginal system, we examined data from participants' daily diaries for documentation of complete ring expulsion. We modeled the odds of reported expulsions over time with adjustment for background and demographic characteristics using mixed-effects logistic regression models with random intercepts. We compared the probability of continuation between those who did and those who did not report expulsions in the first cycle of use using survival analysis and hazards modeling. To determine if expulsions during the first cycle of use affected the risk for pregnancy, we calculated Pearl Indices.

RESULTS

Most participants (75%) never experienced any expulsions during any cycle of use, and 91% to 97% did not experience an expulsion during any 1 cycle. The incidence of expulsion was highest in cycle 1 (9%). The odds of experiencing expulsions decreased by half in cycles 2 to 8 when compared with cycle 1 (0.48; 95% confidence interval, 0.40-0.58), and in cycles 9 to 13, expulsions were about a third of that in cycle 1 (0.32; 95% confidence interval, 0.26-0.41). Of those who did experience expulsions, most (62%-84%) experienced ≤2 expulsions per cycle. Participants from study sites in Latin America vs those in the United States had higher odds of not experiencing an expulsion (odds ratio, 1.95; 95% confidence interval, 1.45-2.63). Women with a higher education level had higher odds of experiencing an expulsion. Notably, parity, age, and body mass index were not associated with expulsion. Participants who experienced any expulsions in cycle 1 were more likely to discontinue use early (hazard ratio, 1.28; 95% confidence interval, 1.14-1.43) than participants who did not have an expulsion. The Pearl Index for participants who had expulsions during cycle 1 was 3.99 (95% confidence interval, 1.29-9.31), which was higher than that among participants who reported no expulsions (Pearl Index, 2.39; 95% confidence interval, 1.61-3.41), but the overlapping confidence intervals indicate that there is not sufficient evidence to demonstrate an association between expulsions and pregnancy risk.

CONCLUSION

Expulsions were infrequent overall, decreased with subsequent cycles of use, and were not associated with body mass index or parity. Early discontinuation of product use was higher among participants who experienced an expulsion during cycle 1. Although it is unclear whether pregnancy risk was associated with expulsions, early recognition of expulsions among users may identify those at higher risk for discontinuation and may highlight when enhanced anticipatory counselling and guidance may be advantageous.

Satisfaction with a Segesterone Acetate and Ethinyl Estradiol Contraceptive Vaginal System Among Recent Oral Contraceptive or Hormonal Contraceptive Vaginal Ring Users

Background: We evaluated satisfaction with use of a segesterone acetate and ethinyl estradiol (0.15/0.013 mg) contraceptive vaginal system (CVS) among women who had recently used a monthly contraceptive vaginal ring or contraceptive pills. The CVS is a ring-shaped device used in a 21-days-in/7-days-out regimen for 13 cycles. Materials and Methods: We analyzed post hoc satisfaction responses at cycle 3 and end of study (EOS) from a subset of participants with documented recent use of the monthly ring or daily pills before enrollment in a multinational, phase 3, 13-cycle trial evaluating the CVS. EOS included results from participants who had completed ≥10 cycles. Results were summarized descriptively. Results: We identified 128 recent ring and 219 recent pill users at cycle 3 (of 1033 survey participants), and 92 and 148, respectively, at EOS (of 622 survey participants); overall satisfaction with CVS use was high (≥90%). At EOS, most ring (89%) and pill (97%) users liked the CVS as much/better than any previous method. The two most-liked CVS features included ease of use and 1-year duration; the two most disliked features included ring insertion and feeling it coming out. At EOS, ≥88% of both groups reported no concern about using the same CVS for a year, and most (>80%) had recommended it to friends or family members. Conclusion: The CVS clinical trial participants who were recent ring/pill users reported high satisfaction and liked it as much/better than any previously used contraceptive; the CVS may be a good contraceptive option for switchers. Clinical trial registration NCT00263341.

Acceptability and Satisfaction of Contraceptive Vaginal Rings in Clinical Studies: A Systematic Review and Narrative Synthesis

Introduction: Acceptability of and satisfaction with contraceptive methods are paramount for uptake and continuation. In the current context of multipurpose prevention of pregnancy and sexually transmitted diseases/HIV development, it is critical to have a better understanding of acceptability of and satisfaction with the contraceptive vaginal ring (CVR) including sexual satisfaction. The objective of this study was to review the evidence about acceptability of CVRs and general and sexual satisfaction of users. Methods: We searched PubMed, CINAHL, and Web of Science (until December 31, 2020) and selected original studies documenting actual use of hormonal CVR and explicitly addressing any of the 3 outcomes. Results: Of a total of 1,129 records screened, 46 studies were included. Most studies (n = 43, 93%) were prospective, conducted in high-income settings (n = 35), and reported on NuvaRing^® use (n = 31). Overall, 27 (59%) studies included a comparison group, 38 (82%) studies used exclusively quantitative questionnaires, with qualitative only (n = 4, 9%), or mixed methods (n = 4, 9%) studies being less common. Ease of CVR insertion/removal/reinsertion was high in all the settings and improved with time of use, with qualitative studies supporting these findings. When mentioned, ring-related events were associated with discontinuation, and results on continuation of use were mixed. Among NuvaRing^® studies, general satisfaction (being satisfied or very satisfied) was between 80 and 90% and tended to mirror continuation. Sexual satisfaction was less commonly reported and results were mixed. Overall, limited information was provided on actual CVR experiences of women (and men) and cultural norms that may affect sexuality and CVR use. Conclusion: Positive aspects of acceptability of and satisfaction with CVRs were reported, but ring-related events and factors, which may affect long-term CVR use, deserve further study. More information is needed on actual experiences of women using CVRs, relationship aspects, male partner opinions, and contextual norms to better understand the acceptability of and satisfaction with CVRs.

The Promise of the Dual Prevention Pill: A Framework for Development and Introduction

Women of reproductive age need multipurpose prevention technology (MPT) products to address two overlapping health risks: unintended pregnancy and HIV. Currently, condoms are the only available MPT, however male condoms are not within the control of a woman, and the use of female condoms has been limited by low acceptability and cost. Oral pre-exposure prophylaxis (PrEP) is highly effective for HIV prevention, yet uptake and adherence among women have been low to date. Women globally need more options for HIV and pregnancy prevention. Several MPTs for simultaneous HIV and pregnancy prevention are in various stages of development and clinical testing, although most are many years away from market launch. A dual prevention pill (DPP), a daily oral pill combining oral contraceptives and PrEP, both of which are licensed, approved products in many low- and middle-income countries (LMIC), is likely to be the fastest route to getting an MPT product into the hands of women. The DPP is one option that could enhance method choice, particularly for women who are already using oral contraceptives. By leveraging the oral contraceptive market and reaching women currently using condoms or with an unmet need for contraception, the DPP has the potential to increase the uptake of PrEP. The successful rollout of the DPP will require careful consideration of user-, provider-, and product-centered factors during product development and introduction. Early attention to these interrelated factors can help ensure that the DPP has the ideal characteristics for maximum product acceptability, that effective and quality services are designed and implemented, and that users can make informed choices, demand the product, and use it effectively. The proposed framework outlines key considerations for the effective development and introduction of the DPP, which could also facilitate integration models for future MPTs.

Context-acceptability theories: example of family planning interventions in five African countries

BACKGROUND

Family planning (FP) can lengthen birth intervals and potentially reduce the risk of foetal death, low birthweight, prematurity, and being small for gestational age. Effective FP is most easily achieved through access to and acceptability of modern contraceptive methods (MCMs). This study aimed to identify mechanisms of acceptability and the contexts in which they are triggered and to generate theories to improve the selection and implementation of effective interventions by studying an intervention integrating FP with childhood immunisation services.

METHODS

Qualitative interpretative synthesis of findings from realist evaluations of FP interventions in five African countries was guided by an analytical framework. Empirical mechanisms of acceptability were identified from semi-structured interviews and focus group discussions with key stakeholders (N = 253). The context in which these mechanisms were triggered was also defined. Empirical mechanisms of acceptability were matched to constructs of a theoretical framework of acceptability. Context-acceptability theories (CATs) were developed, which summarised constructs of acceptability triggered for specific actors in specified contexts. Examples of interventions that may be used to trigger acceptability for these actors were described.

RESULTS

Seven CATs were developed for contexts with strong beliefs in religious values and with powerful religious leaders, a traditional desire for large families, stigmatisation of MCM use, male partners who are non-accepting of FP, and rumours or experiences of MCM side effects. Acceptability mechanisms included alignment with values and beliefs without requiring compromise, actors' certainty about their ability to avoid harm and make the intervention work, and understanding the intervention and how it works. Additionally, acceptability by one group of actors was found to alter the context, triggering acceptability mechanisms amongst others.

CONCLUSIONS

This study demonstrated the value of embedding realist approaches within implementation research. CATs are transferable theories that answer the question: given the context, what construct of acceptability does an intervention need to trigger, or more simply, what intervention do we need to apply here to achieve our outcomes? CATs facilitate transfer of interventions across geographies within defined contexts.

Vaginal Administration of Contraceptives

While contraceptive drugs have enabled many people to decide when they want to have a baby, more than 100 million unintended pregnancies each year in the world may indicate the contraceptive requirement of many people has not been well addressed yet. The vagina is a well-established and practical route for the delivery of various pharmacological molecules, including contraceptives. This review aims to present an overview of different contraceptive methods focusing on the vaginal route of delivery for contraceptives, including current developments, discussing the potentials and limitations of the modern methods, designs, and how well each method performs for delivering the contraceptives and preventing pregnancy.

Long-Lasting, Patient-Controlled, Procedure-Free Contraception: A Review of Annovera with a Pharmacist Perspective

Annovera (segesterone acetate and ethinyl estradiol vaginal system) is a US Food and Drug Administration FDA-approved long-lasting, reversible contraceptive that is fully administered by the user and does not require a procedure for insertion or removal. The vaginal system is in the shape of a ring and contains low doses of a novel progestin, egesterone acetate, and ethinyl estradiol. It is made of silicone and is fully pliable and flexible. The vaginal system is reusable for 13 cycles, using a 21 days in/7 days out regimen, providing women with the ability to control their fertility. Particularly now during the COVID-19 pandemic when access to contraception has been further reduced, patients may benefit from a method that is both long-lasting and patient-controlled.

Vaginal probiotic adherence and acceptability in Rwandan women with high sexual risk participating in a pilot randomised controlled trial: a mixed-methods approach

OBJECTIVES

To evaluate adherence and acceptability of intermittent vaginal probiotic or antibiotic use to prevent bacterial vaginosis (BV) recurrence.

DESIGN

Repeated adherence and acceptability assessments using mixed methods within a pilot randomised controlled trial.

SETTING

Research clinic in Kigali, Rwanda.

PARTICIPANTS

Rwandan women with high sexual risk.

INTERVENTIONS

Women diagnosed with BV and/or trichomoniasis were randomised to four groups (n=17 each) after completing metronidazole treatment: behavioural counselling only, or behavioural counselling plus 2-month intermittent use of oral metronidazole, Ecologic Femi+ (EF+) vaginal capsule or Gynophilus LP (GynLP) vaginal tablet.

OUTCOME MEASURES

Adherence and acceptability were assessed by structured face-to-face interviews, semi-structured focus group discussions and in-depth interviews, daily diaries and counting of used/unused study products in randomised women (n=68). Vaginal infection knowledge was assessed by structured face-to-face interviews in randomised women and women attending recruitment sessions (n=131).

RESULTS

Most women (93%) were sex workers, 99.2% were unfamiliar with BV and none had ever used probiotics. All probiotic users (n=32) reported that insertion became easier over time. Triangulated adherence data showed that 17/17 EF+ users and 13/16 GynLP users used ≥80% of required doses (Fisher's exact p=0.103). Younger age (p=0.076), asking many questions at enrolment (p=0.116), having menses (p=0.104) and reporting urogenital symptoms (p=0.103) were non-significantly associated with lower perfect adherence. Women believed that the probiotics reduced BV recurrence, but reported that partners were sometimes unsupportive of study participation. Self-reported vaginal washing practices decreased during follow-up, but sexual risk behaviours did not. Most women (12/15) with an uncircumcised steady partner discussed penile hygiene with him, but many women found this difficult, especially with male clients.

CONCLUSIONS

High-risk women require education about vaginal infections. Vaginal probiotic acceptability and adherence were high in this cohort. Our results can be used to inform future product development and to fine-tune counselling messages in prevention programmes.

TRIAL REGISTRATION NUMBER

NCT02459665.

Dose-finding study of a 90-day contraceptive vaginal ring releasing estradiol and segesterone acetate

OBJECTIVE

To evaluate serum estradiol (E2) concentrations during use of 90-day contraceptive vaginal rings releasing E2 75, 100, or 200 mcg/day and segesterone acetate (SA) 200 mcg/day to identify a dose that avoids hypoestrogenism.

STUDY DESIGN

We conducted a multicenter dose-finding study in healthy, reproductive-aged women with regular cycles with sequential enrollment to increasing E2 dose groups. We evaluated serum E2 concentrations twice weekly for the primary outcome of median E2 concentrations throughout initial 30-day use (target ≥40 pg/mL). In an optional 2-cycle extension substudy, we randomized participants to 2- or 4-day ring-free intervals per 30-day cycle to evaluate bleeding and spotting based on daily diary information.

RESULTS

Sixty-five participants enrolled in E2 75 (n = 22), 100 (n = 21), and 200 (n = 22) mcg/day groups; 35 participated in the substudy. Median serum E2 concentrations in 75 and 100 mcg/day groups were <40 pg/mL. In the 200 mcg/day group, median E2 concentrations peaked on days 4-5 of CVR use at 194 pg/mL (range 114-312 pg/mL) and remained >40 pg/mL throughout 30 days; E2 concentrations were 37 pg/mL (range 28-62 pg/mL) on days 88-90 (n = 11). Among the E2 200 mcg/day substudy participants, all had withdrawal bleeding following ring removal. The 2-day ring-free interval group reported zero median unscheduled bleeding and two (range 0-16) and three (range 0-19) unscheduled spotting days in extension cycles 1 and 2, respectively. The 4-day ring-free interval group reported zero median unscheduled bleeding or spotting days.

CONCLUSIONS

Estradiol concentrations with rings releasing E2 200 mcg/day and SA 200 mcg/day avoid hypoestrogenism over 30-day use.

IMPLICATIONS

A 90-day contraceptive vaginal ring releasing estradiol 200 mcg/day and segesterone acetate 200 mcg/day achieves estradiol concentrations that should avoid hypoestrogenism and effectively suppresses ovulation.

A technology evaluation of Annovera: a segesterone acetate and ethinyl estradiol vaginal ring used to prevent pregnancy for up to one year

INTRODUCTION

The segesterone acetate and ethinyl estradiol contraceptive vaginal ring (SA/EE CVR) was FDA-approved in August 2018 and is now available in the U.S. The CVR is placed vaginally for 21 days followed by a 7-day ring-free interval, when withdrawal bleeding typically occurs. One ring can be used for up to a year (13 cycles).

AREAS COVERED

This review summarizes this novel method of contraception, including the delivery system and the hormonal components. We describe the potential market, how it is used, the pharmacokinetic properties of the device, and results of clinical trials including efficacy, bleeding profile, acceptability, and safety.

EXPERT OPINION

The SA/EE CVR represents the first long-lasting user-controlled hormonal contraceptive device. The bleeding pattern is highly favorable and consistent over the entire year and is associated with very low discontinuation. Efficacy and safety are similar to other methods of combined hormonal contraceptives. Unscheduled ring removals increase the risk of failure. Further studies are needed to evaluate continuous use of the ring for greater than 21 days, and potential non-contraceptive benefits of the ring such as reduced menstrual bleeding.

Progesterone vaginal ring as a new contraceptive option for lactating mothers: Evidence from a multicenter non-randomized comparative clinical trial in India

OBJECTIVES

Evaluate and compare contraceptive efficacy, safety, continuation rates and duration of lactational amenorrhea (LA) in married lactating women (20-35 years) using the progesterone vaginal ring (PVR) or Copper-T380A intrauterine device (IUD) during the first postpartum year.

STUDY DESIGN

We conducted a one-year multicenter, non-randomized, non-inferiority, open-label, comparative trial at 20 centers in India and compared efficacy, safety, continuation and LA plus feeding patterns and growth/well-being of participants' infants. Women used four 3-month PVRs consecutively (lost PVRs were not replaced) and were to breastfeed at least four times/day. We used Pearl Index (PI) and Kaplan Meier (K-M) rates to analyze pregnancy and K-M for continuation.

RESULTS

We enrolled 789 women (459 PVR, 330 IUD). Neither PI nor K-M one-year pregnancy rates differed significantly between groups (PI: PVR-0.62; IUD-0.35); (K-M: PVR-0.7; IUD-0.4, p = 0.58). Continuation rates at 12 months were 78.5% (IUD) vs. 56.9% (PVR) (p < 0.001). Ring expulsions and menorrhagia were the most common discontinuation among PVR/IUD users respectively. The median duration of LA among PVR vs. IUD users was 405 vs. 120 days (p < 0.001). Both groups reported similar adverse events (PVR: 24.2%; IUD: 23.0%); there were no serious adverse events among PVR users. Infants from both groups fed 12-7 times/day and grew at expected rates.

CONCLUSIONS

Efficacy and safety outcomes were comparable among women in both groups. Continuation rates for PVR, a woman-controlled method, were shorter than IUD rates while PVR users maintained LA significantly longer than IUD users. Infant breastfeeding and growth patterns/well-being were favorable in both groups.

IMPLICATIONS

PVR, a user-controlled device, offers an additional contraceptive choice for lactating women for one-year postpartum use and can help to address the unmet need for contraception among postpartum women while encouraging breastfeeding to enhance infant growth and well-being.

Choosing and Using the Progesterone Vaginal Ring: Women's Lived Experiences in Three African Cities

PURPOSE

This study explored experiences of selecting and utilizing a newly introduced contraceptive - the progesterone vaginal ring (PVR) - among women seeking a contraceptive method in 3 African capital cities (Abuja, Nairobi, and Senegal). The study explored women's perceptions of, and lived experiences with, using the new product to better understand their reception of a new contraceptive. This understanding will help inform the design of programs to support women in their adoption and continued use of the PVR and other new contraceptives.

PATIENTS AND METHODS

This longitudinal, qualitative study drew on an interpretive phenomenological approach, involving multiple in-depth interviews (IDIs) with 9 study participants over a 6-month period. Participants involved in the study were postpartum women seeking contraceptive services at participating clinics. A total of 25 IDIs were conducted, and a detailed "within-case" and "cross-case" analysis of participants' accounts was carried out to identify similar and dissimilar themes along descriptive, linguistic, and conceptual lines.

RESULTS

Four overarching themes emerged from the analysis. These themes circulated around the unconventionality of the PVR, which heightened its desirability among participants; the sense of comfort that women gained from opting to use the PVR over other FP methods; narratives of consideration that centered on women's partners, and that were important for ensuring the sustainability of women's PVR use; and the conundrums that women grappled with as they prepared to disengage from the PVR after two cycles of use.

CONCLUSION

The PVR is an acceptable contraceptive method to postpartum women in urban African settings. However, prior to its introduction into new country contexts, formative data on women's perceptions of, and reactions to, the product need to inform country preparation processes. Such information would be useful for tailoring counseling around this contraceptive, as well as for product marketing and robust uptake of the method.

Bleeding profile associated with 1-year use of the segesterone acetate/ethinyl estradiol contraceptive vaginal system: pooled analysis from Phase 3 trials

OBJECTIVES

To describe bleeding patterns among users of the segesterone acetate (SA) and ethinyl estradiol (EE) contraceptive vaginal system (CVS), and identify factors associated with unscheduled bleeding/spotting (B/S).

STUDY DESIGN

We pooled results from two multicenter, single-arm, open-label, pivotal, phase 3 studies of the SA/EE CVS conducted in 17 US and 7 international sites. Participants (age 18-40 years; BMI ≤29 kg/m2) followed a 21/7-day in/out schedule of CVS use for up to 13 cycles and recorded vaginal bleeding daily in paper diaries. Scheduled and unscheduled B/S were summarized by cycle. We used multiple logistic regression to identify factors associated with unscheduled bleeding/spotting, based on the first 4 cycles only.

RESULTS

Analysis included data from 2070 participants (16,408 cycles). Ninety-eight percent documented scheduled B/S [mean (SD): 4.9 (1.1) days/cycle)]. Absence of scheduled B/S was 5-8% of women/cycle. Unscheduled B/S ranged from 13.2% to 21.7% of women per cycle. Few women (1.8%) discontinued prematurely due to unacceptable bleeding. Black women were more likely to report unscheduled B/S than White women [Adjusted odds ratio (AOR) = 1.49, 95% confidence interval (CI) = 1.14-1.94]. Women with fewer years of schooling [

CONCLUSIONS

Participants using the SA/EE CVS up to 13 cycles reported good cycle control. Discontinuation due to unacceptable bleeding was very low. Further research into demographic/other differences with reported unscheduled bleeding is warranted.

IMPLICATIONS

Since good cycle control is a key factor influencing contraceptive selection, adherence and continuation of combined hormonal contraceptives, the favorable bleeding profiles experienced by women during the SA/EE CVS clinical trials provide reassuring information for prospective users.

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Key Words

• Bleeding patterns
• Combined hormonal contraceptives
• Contraceptive vaginal system
• Nestorone
• Segesterone acetate

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MESH Headings

• Adolescent
• Adult
• Drug Combinations
• Ethinyl Estradiol/adverse effects
• Female
• Humans
• Menstruation/drug effects
• Pregnenediones/adverse effects
• Young Adult

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Grants

• HD43379003 NICHD NIH HHS
• HD43374003 NICHD NIH HHS
• HD43371003 NICHD NIH HHS
• HD43372003 NICHD NIH HHS
• HD43382003 NICHD NIH HHS
• HD43376003 NICHD NIH HHS
• HD43375003 NICHD NIH HHS
• HD43378003 NICHD NIH HHS
• HD43381003 NIDDK NIH HHS
• HD43373003 NICHD NIH HHS
• HD43366003 NICHD NIH HHS
• HD43377003 NICHD NIH HHS
• HD43380003 NCI NIH HHS

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Affiliation(s)

Carolina Sales Vieira Department of Gynecology and Obstetrics, Ribeirao Preto Medical School, University of São Paulo, Avenida Bandeirantes, 3900 - Campus Universitário - Monte Alegre, CEP: 14049-900, Ribeirão Preto, SP, Brazil.; Population Council, 1230 York Avenue, New York City, NY, 10065, USA..
Ian S Fraser The University of New South Wales, School of Women's and Children's Health, Royal Hospital for Women, Barker Street, Randwick, NSW 2031, Australia
Marlena G Plagianos Population Council, 1230 York Avenue, New York City, NY, 10065, USA
Anne E Burke Department of Gynecology and Obstetrics, the Johns Hopkins University School of Medicine, Bayview Medical Center, Baltimore, MD 21224, USA
Carolyn L Westhoff Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, New York City, NY 10032, USA
Jeffrey Jensen Department of Obstetrics & Gynecology, Oregon Health & Science University, Portland, OR, 97239, USA
Vivian Brache Profamilia, Santo Domingo, Dominican Republic
Luis Bahamondes Department of Obstetrics and Gynecology, Faculty of Medical Science, University of Campinas, Caixa Postal 6181, CEP 13084-971, Campinas, SP, Brazil
Ruth Merkatz Population Council, 1230 York Avenue, New York City, NY, 10065, USA
Regine Sitruk-Ware Population Council, 1230 York Avenue, New York City, NY, 10065, USA
Diana L Blithe Contraceptive Development Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA

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A Qualitative Systematic Review of Women's Experiences Using Contraceptive Vaginal Rings: Implications for New Technologies

CONTEXT

Vaginal rings are available for contraception and hormone replacement, and are being developed as HIV/STD or multipurpose prevention technologies. A comprehensive understanding of women's expectations of and experiences with rings is urgently needed to inform product development and to optimize ring use.

METHODS

Three databases (PubMed, Global Health and CINAHL) were searched for English-language, peer-reviewed articles published between January 1996 and November 2017 that reported qualitative data on barriers to and facilitators of use of female-controlled contraceptive methods. Data on study methods, findings and conclusions pertaining to contraceptive rings were extracted, organized and analyzed.

RESULTS

Twenty-six articles, all published since 2008, met the inclusion criteria. Seven studies focused largely or entirely on rings (and involved current, former or potential users), while the others focused on other contraceptive methods but included ring-specific data. Familiarity with the ring was low, and women commonly had initial concerns about the method-often related to insertion and removal, cleanliness and discomfort with touching their vagina-that were typically overcome over time. Other major themes were issues related to ring use and discontinuation, the importance of ring-related properties and characteristics, and considerations related to sexual partners and health care providers.

CONCLUSIONS

Qualitative data have the potential to inform ring design and promotion. Future research should further explore women's expectations and experiences with the ring, the value of involving male partners in ring evaluation, and evaluation of interventions to improve patient-provider communication concerning ring choice and use.

Topical Inserts: A Versatile Delivery Form for HIV Prevention

The development of topical inserts for the prevention of sexually transmitted infections (STIs), particularly human immunodeficiency virus (HIV), represents a promising alternative to oral and parenteral pre-exposure prophylaxis (PrEP) dosage forms. They may be used for vaginal and/or rectal administration of a variety of agents with antiviral activity. Topical inserts deliver drugs to the portal of viral entry, i.e., the genital or rectal mucosa, with low systemic exposure, and therefore are safer and have fewer side effects than systemic PrEP agents. They may dissolve fast, releasing the active drugs within minutes of insertion, or slowly for long-acting drug delivery. Furthermore, they are user-friendly being easy to administer, discreet and highly portable. They are also economical and easy to manufacture at scale and to distribute, with excellent stability and shelf-life. Altogether, topical inserts represent a particularly promising form of drug delivery for HIV and STI prevention. Highlighted within this review are end-user acceptability research dedicated to understanding preferred attributes for this form of drug delivery, advantages and disadvantages of the formulation platform options, considerations for their development, clinical assessment of select placebo prototypes, future directions, and the potential impact of this dosage form on the HIV prevention landscape.

Towards a dapivirine and levonorgestrel multipurpose vaginal ring: Investigations into the reaction between levonorgestrel and addition-cure silicone elastomers

With a dapivirine-releasing vaginal ring having successfully completed late-stage clinical testing for HIV prevention and currently undergoing regulatory review, there is now growing interest in next-generation multipurpose prevention technologies that seek to combine antiretroviral and contraceptive drugs within a single product. Here, we focus on ongoing efforts to develop a silicone elastomer vaginal ring releasing both dapivirine and levonorgestrel. Specifically, we evaluate various strategies aimed at both better understanding and reducing the tendency of levonorgestrel to bind with the elastomer, including: (i) formulation and post-manufacturing strategies aimed at reducing the extent of levonorgestrel reaction with addition-cure silicone elastomers; (ii) evaluation of a simple silicone system to model the complex elastomer; (iii) use of model compounds representing the enone and ethinyl moieties of levonorgestrel to probe the mode of addition of levonorgestrel to addition-cure silicone elastomers; and (iv) solution and solid-state ¹³C NMR analysis to probe the structural features of the levonorgestrel-silicone system. The results demonstrate that both the enone and ethinyl groups within levonorgestrel undergo hydrosilylation reactions with the hydrosiloxane groups in the silicone elastomer leading to covalent binding. The results also highlight potential strategies for further optimising the dapivirine + levonorgestrel silicone vaginal ring formulation to ensure that the levonorgestrel is available for release.

A Qualitative Systematic Review of Women's Experiences Using Contraceptive Vaginal Rings: Implications for New Technologies

CONTEXT

Vaginal rings are available for contraception and hormone replacement, and are being developed as HIV/STD or multipurpose prevention technologies. A comprehensive understanding of women's expectations of and experiences with rings is urgently needed to inform product development and to optimize ring use.

METHODS

Three databases (PubMed, Global Health and CINAHL) were searched for English-language, peer-reviewed articles published between January 1996 and November 2017 that reported qualitative data on barriers to and facilitators of use of female-controlled contraceptive methods. Data on study methods, findings and conclusions pertaining to contraceptive rings were extracted, organized and analyzed.

RESULTS

Twenty-six articles, all published since 2008, met the inclusion criteria. Seven studies focused largely or entirely on rings (and involved current, former or potential users), while the others focused on other contraceptive methods but included ring-specific data. Familiarity with the ring was low, and women commonly had initial concerns about the method-often related to insertion and removal, cleanliness and discomfort with touching their vagina-that were typically overcome over time. Other major themes were issues related to ring use and discontinuation, the importance of ring-related properties and characteristics, and considerations related to sexual partners and health care providers.

CONCLUSIONS

Qualitative data have the potential to inform ring design and promotion. Future research should further explore women's expectations and experiences with the ring, the value of involving male partners in ring evaluation, and evaluation of interventions to improve patient-provider communication concerning ring choice and use.

Qualitative exploration of intrinsic and extrinsic factors that influence acceptability of semisoft vaginal suppositories

BACKGROUND

Vaginal microbicides are a promising means to prevent the transmission of HIV and other sexually transmitted infections, by empowering women to initiate use prophylactically when they perceive themselves to be at risk. However, in clinical trials, microbicides have shown mixed results, with the consistent finding that effectiveness varies substantially as a function of user adherence.

METHODS

Based on the assumption that adherence is driven, at least in part, by product properties that influence acceptability, we used softgel technology to develop vaginal drug delivery systems in the intermediate texture space between solids and liquids to overcome potential shortcomings of current dosage forms. Here, we used focus groups and surveys to determine women's initial reactions (i.e., acceptance and willingness-to-try) for semisoft vaginal suppositories intended for HIV and STI prevention, with a specific focus on how perception of and preferences for vaginal suppositories may be influenced by product characteristics such as size, shape, and firmness.

RESULTS

Via focus groups, we identified intrinsic and extrinsic factors relevant to acceptability of semisoft suppository prototypes. Willingness-to-try depended on factors like intended functionality, anticipated leakage, type of sex, recommended frequency of use, type of sexual partner, and perceived risk. When handled ex vivo, shape, size, and firmness of suppositories communicated information about ease of imagined insertion and handling, perceived effectiveness, anticipated awareness and comfort of the product in the body. These impressions were partly based on prior experience with vaginal products.

CONCLUSIONS

Sensory attributes appear to play a substantial role in women's preferences and willingness to try the semisoft suppositories. Using these methods during preclinical development should help efficiently optimize a final product that is both biologically efficacious and preferred by women, toward a goal of enhancing adherence and effectiveness.

Advances in contraceptive vaginal rings: what does the future hold?

INTRODUCTION

Contraceptive vaginal rings (CVRs) are good contraceptive options because they do not require skilled providers, are self-administered, and show a higher stability of drug diffusion.

AREAS COVERED

This article provides a review of the developments made with CVRs over the past number of years, while giving focus to the latest CVRs that have gone through clinical development. The author of the article also provides an expert perspective on the future of these useful therapeutic options.

EXPERT OPINION

Pharmacokinetic studies have shown that segesterone, an absorbable progestin that is used alone or in combination with ethinyl estradiol (EE) or E_2, is the CVR of choice at this present time. Indeed, segesterone has demonstrated safety and efficacy as a CVR and is also an appropriate option for lactating women, as they are not absorbed orally. However, good cycle control is important for improved CVR adherence. CVRs that allow the combination of more than one drug may unravel another multi-purpose use when combined with microbicides and could provide combined protection to women who wish to protect themselves from pregnancy and sexually transmitted infection.

Solid state 13C NMR spectroscopy provides direct evidence for reaction between ethinyl estradiol and a silicone elastomer vaginal ring drug delivery system

Steroid molecules have a long history of incorporation into silicone elastomer materials for controlled release drug delivery applications. Previously, based on in vitro release testing and drug content analysis, we demonstrated indirectly that the contraceptive progestin levonorgestrel (LNG) chemically and irreversibly binds to addition cure silicone elastomers, presumably via a hydrosilylation reaction between the levonorgestrel ethynyl group and the hydrosilane groups in the poly(dimethylsiloxane-co-methylhydrosiloxane) crosslinker of the silicone elastomer. Here, for the first time, we report that solid state ¹³C nuclear magnetic resonance (NMR) spectroscopy provides direct evidence for the irreversible binding of ethinyl estradiol (EE) - an estrogenic steroid molecule also containing an ethynyl functional group - to an addition cure silicone elastomer. By preparing silicone elastomer samples containing ¹³C-labelled EE, signals in the NMR spectra could readily be assigned to both the free and bound EE. Additional depolymerisation studies, performed on an addition cure silicone elastomer system from which the unbound EE fraction was completely extracted, further confirmed the presence of bound EE through the formation of coloured reaction mixtures resulting from the reaction of bound EE and trifluoroacetic acid (TFA). These methods will be particularly useful in the ongoing development of new steroid-releasing silicone drug delivery devices, including various vaginal ring devices for contraception, HIV prevention and multipurpose prevention technology applications.

High acceptability of a contraceptive vaginal ring among women in Kigali, Rwanda

BACKGROUND

Introduction of contraceptive vaginal rings (CVRs) could expand the contraceptive method mix reducing the unmet need for family planning in Rwanda, but data on acceptability of CVRs from low and middle-income countries are lacking.

METHODS

This study explores acceptability of contraceptive vaginal ring (NuvaRing) use in Kigali, Rwanda using a mixed methods approach. We collected quantitative and qualitative data before, during and after conducting a clinical trial, using Case Report Forms, Interviewer Administered Questionnaires, In Depth Interviews and Focus Group Discussions. We analyzed the data using an existing theoretical framework including product attributes, relationship attributes and sexual encounter attributes as well as the contextual environment.

RESULTS

Our data showed that initial worries reduced over time with actual ring use and ring insertions and removals were described as easy. Most women did not feel the ring during daily activities, appreciated the lack of perceived negative side effects and the increased lubrication. Relationship attributes and sexual encounter attributes such as sexual comfort played a significant role in ring acceptability of the participants and their partners. The contextual environment including Rwandan cultural norms around sexuality positively influenced the acceptance of the NuvaRing. Overall satisfaction was high.

CONCLUSIONS

Acceptability of the Nuvaring was high among study participants and represents a promising option that could contribute to lowering the unmet need for family planning in Rwanda.

Acceptability of a Tenofovir Disoproxil Fumarate Vaginal Ring for HIV Prevention Among Women in New York City

Vaginal rings for pre-exposure prophylaxis are a female-initiated HIV prevention method that does not require daily or coitally-dependent dosing. As part of a randomized placebo-controlled trial of a tenofovir disoproxil fumarate intravaginal ring, we assessed product acceptability through in-depth interviews with 18 women during and after 14 days of continuous use. Women reported that the ring was comfortable with few side effects, regardless of experimental arm. However, interest in future use by this cohort was modest for several reasons including: low self-perceived HIV risk; concern that use implied promiscuity; potential for interference with relationship formation and trust; concern for interference with menstruation and cleanliness; and worries about partners' acceptability and sexual pleasure. Potential issues were raised with duration of use prior to ring exchange. Future studies should continue to identify and address individual and relationship factors that influence acceptability, early in the product development process.

Factors associated with nonadherence to instructions for using the Nestorone®/ethinyl estradiol contraceptive vaginal ring

OBJECTIVES

We sought to identify factors associated with nonadherence to instructions for using a novel contraceptive providing 1 year of protection.

STUDY DESIGN

Data from a multicountry Phase 3 trial of the Nestorone® (segesterone acetate)/ethinyl estradiol (NES/EE) contraceptive vaginal ring (CVR) were analyzed. Participants were instructed to use the CVR over 13 cycles and follow a 21/7 regimen. Their reports of CVR removals >2 h outside scheduled removal periods served as a proxy for nonadherence. We used multivariate logistic regression to determine factors associated with such use.

RESULTS

Of 905 participants, 120 (13%) reported CVR removals >2 h. Removals for washing [odds ratio (OR) 3.96, 95% confidence interval (CI) 2.50-6.27] or sexual intercourse (OR 3.19, 95% CI 2.03-4.99), and finding CVR insertion difficult (OR 2.80, 95% CI 1.36-5.80) were factors associated with removals >2 h. Lower educational attainment also predicted ring removal >2 h (OR 3.23, 95% CI 1.55-6.75). Women residing in Europe or Australia were less likely to remove the ring for >2 h compared with women in the United States (OR 0.44, 95% CI 0.24-0.83 and OR 0.13, 95% CI 0.02-0.98, respectively). Participants who reported removals >2 h were more likely to discontinue CVR use (OR 1.93, 95% CI 1.24-2.95), report dissatisfaction (OR 2.20, 95% CI 1.32-3.69) and become pregnant during the study (OR 4.07, 95% CI 1.58-10.50).

CONCLUSIONS

Removing the CVR for washing and removing it before intercourse are factors associated with nonadherence to ring use. These are important topics for counseling women who are considering or using vaginal rings, including the NES/EE CVR.

IMPLICATIONS

Findings from this study may be useful in guiding counseling for current and prospective vaginal ring users. Anticipatory guidance should focus on how the ring feels in the vagina and during sex. Asking about ring removals may help identify women who are at increased risk for having an unplanned pregnancy.

Pipeline for contraceptive development

The high rates of unplanned pregnancy reflect an unmet need for effective contraceptive methods for women, especially for individuals with health risks such as obesity, diabetes, hypertension, and other conditions that may contraindicate use of an estrogen-containing product. Improvements in safety, user convenience, acceptability, and availability of products remain important goals of the contraceptive development program. Another important goal is to minimize the impact of the products on the environment. Development of new methods for male contraception has the potential to address many of these issues of safety for women who have contraindications to effective contraceptive methods but want to protect against pregnancy. It would also address a huge unmet need for men who want to control their fertility. Products under development for men would not introduce ecotoxic hormones into the water system.

The Sexual Acceptability of Contraception: Reviewing the Literature and Building a New Concept

How contraceptives affect women's sexual well-being is critically understudied. Fortunately, a growing literature focuses on sexual aspects of contraception, especially hormonal contraception's associations with libido. However, a more holistic approach to contraceptive sexual acceptability is needed to capture the full range of women's sexual experiences. We conducted a narrative literature review of this topic, working with an original sample of 3,001 citations published from 2005 to 2015. In Part 1, we draw from a subset of this literature (264 citations) to build a new conceptual model of sexual acceptability. Aspects include macro factors (gender, social inequality, culture, and structure), relationship factors (dyadic influences and partner preferences), and individual factors (sexual functioning, sexual preferences, such as dis/inhibition, spontaneity, pleasure, the sexual aspects of side effects, such as bleeding, mood changes, sexual identity and sexual minority status, and pregnancy intentions). In Part 2, we review the empirical literature on the sexual acceptability of individual methods (103 citations), applying the model as much as possible. Results suggest contraceptives can affect women's sexuality in a wide variety of positive and negative ways that extend beyond sexual functioning alone. More attention to sexual acceptability could promote both women's sexual well-being and more widespread, user-friendly contraceptive practices.

Perceptibility and the "Choice Experience": User Sensory Perceptions and Experiences Inform Vaginal Prevention Product Design

The development of pericoital (on demand) vaginal HIV prevention technologies remains a global health priority. Clinical trials to date have been challenged by nonadherence, leading to an inability to demonstrate product efficacy. The work here provides new methodology and results to begin to address this limitation. We created validated scales that allow users to characterize sensory perceptions and experiences when using vaginal gel formulations. In this study, we sought to understand the user sensory perceptions and experiences (USPEs) that characterize the preferred product experience for each participant. Two hundred four women evaluated four semisolid vaginal formulations using the USPE scales at four randomly ordered formulation evaluation visits. Women were asked to select their preferred formulation experience for HIV prevention among the four formulations evaluated. The scale scores on the Sex-associated USPE scales (e.g., Initial Penetration and Leakage) for each participant's selected formulation were used in a latent class model analysis. Four classes of preferred formulation experiences were identified. Sociodemographic and sexual history variables did not predict class membership; however, four specific scales were significantly related to class: Initial Penetration, Perceived Wetness, Messiness, and Leakage. The range of preferred user experiences represented by the scale scores creates a potential target range for product development, such that products that elicit scale scores that fall within the preferred range may be more acceptable, or tolerable, to the population under study. It is recommended that similar analyses should be conducted with other semisolid vaginal formulations, and in other cultures, to determine product property and development targets.

Acceptability of intrauterine contraception among women living with human immunodeficiency virus: a randomised clinical trial

OBJECTIVES

The aim of our study was to compare acceptability of the copper intrauterine device (Cu-IUD) and levonorgestrel-releasing intrauterine system (LNG-IUS) among women living with the human immunodeficiency virus (HIV).

METHODS

We randomly assigned 703 HIV-positive women in Uganda to receive either a Cu-IUD or an LNG-IUS and followed them for at least one year. During the follow-up visits, face-to-face interviews were conducted with the women and acceptability of the Cu-IUD or LNG-IUS was assessed, using a Likert scale, at one, three, six and twelve months. At the final follow-up visit, women were also assessed for satisfaction with either method.

RESULTS

Between 9 September 2013 and 31 December 2014, 703 women were recruited and assigned as follows: 349 to a Cu-IUD group and 354 to an LNG-IUS group. Acceptability decreased from 94.3% at one month to 87.7% at 12 months in the Cu-IUD group and from 96.3% at one month to 86.7% at 12 months in the LNG-IUS group (p = 0.97). Satisfaction with intrauterine contraception was reported by 83.7% (283/338) in the Cu-IUD group and by 90.4% (302/334) in the LNG-IUS group (p = 0.50).

CONCLUSIONS

There was no significant difference in acceptability between the LNG-IUS and Cu-IUD among HIV-positive women. Satisfaction rates were high and similar in the two groups. Both the Cu-IUD and LNG-IUS are acceptable forms of contraception for HIV-positive women and should be made available to women in HIV care to increase their contraceptive method options.

CLINICAL TRIAL REGISTRATION

The trial is registered at the Pan African Clinical Trials Registry (PACTR 201308000561212).

Effects of a One Year Reusable Contraceptive Vaginal Ring on Vaginal Microflora and the Risk of Vaginal Infection: An Open-Label Prospective Evaluation

BACKGROUND

A contraceptive vaginal ring (CVR) containing Nestorone® (NES) and ethinyl estradiol (EE) that is reusable for 1- year (13 cycles) is under development. This study assessed effects of this investigational CVR on the incidence of vaginal infections and change in vaginal microflora.

METHODS

There were 120 women enrolled into a NES/EE CVR Phase III trial and a microbiology sub-study for up to 1- year of cyclic product use. Gynecological examinations were conducted at baseline, the first week of cycle 6 and last week of cycle 13 (or during early discontinuation visits). Vaginal swabs were obtained for wet mount microscopy, Gram stain and culture. The CVR was removed from the vagina at the last study visit and cultured. Semi-quantitative cultures for Lactobacillus, Gardnerella vaginalis, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, anaerobic gram negative rods (GNRs), Candida albicans and other yeasts were performed on vaginal and CVR samples. Vaginal infections were documented throughout the study.

RESULTS

Over 1- year of use, 3.3% of subjects were clinically diagnosed with bacterial vaginosis, 15.0% with vulvovaginal candidiasis, and 0.8% with trichomoniasis. The detection rate of these three infections did not change significantly from baseline to either Cycle 6 or 13. Nugent scores remained stable. H2O2-positive Lactobacillus dominated vaginal flora with a non-significant prevalence increase from 76.7% at baseline to 82.7% at cycle 6 and 90.2% at cycle 13, and a median concentration of 107 colony forming units (cfu) per gram. Although anaerobic GNRs prevalence increased significantly, the median concentration decreased slightly (104 to 103cfu per gram). There were no significant changes in frequency or concentrations of other pathogens. High levels of agreement between vaginal and ring surface microbiota were observed.

CONCLUSION

Sustained use of the NES/EE CVR did not increase the risk of vaginal infection and was not disruptive to the vaginal ecosystem.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00263341, NCT00455156.

Applying emerging science to contraception research: implications for the clinic

Emerging science will make an important contribution towards the development of improved contraceptives. While long-acting reversible contraceptives remain the most effective method, new user-controlled, mid-acting methods will avoid the need for procedures requiring trained providers. Contraceptives combined with other agents may bring additional health benefits, such as dual protection against both pregnancy and sexually transmitted infections. Emerging research areas in proteomics allowed the discovery of new reproductive targets that may lead to non-hormonal contraceptives for both men and women. Current research objectives include the improvement of existing contraceptive methods, as well as discovery of new materials able to deliver new molecules more specifically to their target without systemic actions.