Evaluating the efficacy and safety of a progestin- and estrogen-releasing ethylene vinyl acetate copolymer contraceptive vaginal ring

Hormonal Contraception and Menstrual Cycle Control at High Altitude: A Scoping Review-UIAA Medical Commission Recommendations

Horakova, Lenka , Susi Kriemler, Vladimír Študent, Jacqueline Pichler Hefti, David Hillebrandt, Dominique Jean, Kastė Mateikaitė-Pipirienė, Peter Paal, Alison Rosier, Marija Andjelkovic, Beth Beidlemann, Mia Derstine, and Linda E. Keyes. Hormonal contraception and menstrual cycle control at high altitude: a scoping review-UIAA Medical Commission recommendations. High Alt Med Biol. 00:00-00, 2024. Background: Women who use hormonal contraception (HC) may have questions about their use during travel to high altitude. This scoping review summarizes current evidence on the efficacy and safety of HC and cycle control during high-altitude travel. Methods: We performed a scoping review for the International Climbing and Mountaineering Federation (UIAA) Medical Commission series on Women's Health in the Mountains. Pertinent literature from PubMed and Cochrane was identified by keyword search combinations (including contraception) with additional publications found by hand search. Results: We identified 17 studies from 7,165 potentially eligible articles. No articles assessed the efficacy of contraception during a short-term high-altitude sojourn. Current data show no advantage or disadvantage in HC users for acclimatization or acute mountain sickness (AMS). Use of HC during high-altitude travel is common and safe for menses suppression. A potential concern of estrogen-containing HC is the increased thrombotic risk, which theoretically could be compounded in hypobaric hypoxia. Conclusions: Evidence is limited for the interaction of HC and high altitude on performance, thrombosis, and contraceptive efficacy. HC does not affect the risk of AMS. The most efficacious and safest method at high altitude is generally the one women are most familiar with and already using.

Endovascular Thrombectomy and Lysis for Acute Renal Vein Thrombosis: Indications, Technical Aspects, Outcome, and Disease Etiology

PURPOSE

To report a rare case of acute renal vein thrombosis (RVT) that was treated with endovascular thrombectomy and lysis, and discuss potential etiology and indications for catheter-directed management.

CASE REPORT

A 21-year-old female athlete presented with sudden pain in her left flank and vomiting. A 3-phase computed tomography (CT) angiogram identified total occlusion of the left renal vein with no excretion from the swollen tender left kidney. Catheter-directed thrombolysis and thrombectomy were initiated 24 hours after onset of symptoms. Complete resolution of the RVT with normalized renal function was achieved. Post-operative Doppler ultrasound scan confirmed normal renal resistance and flow in the renal vein. The patient was discharged on Apixaban and remains well at 6 months. Combined hormonal contraception via an intra-vaginal ring and raised Factor VIII activity were the only identified risk factors.

CONCLUSION

Acute complete RVT with impaired kidney function is rare. Combined hormonal contraception and increased Factor VIII activity were potential risk factors. Endovascular thrombectomy and lysis restored renal perfusion and function, and can be used effectively in the management of fit patients with acutely compromised kidney function from total renal vein obstruction.

Recent progress in advanced biomaterials for long-acting reversible contraception

Unintended pregnancy is a global issue with serious ramifications for women, their families, and society, including abortion, infertility, and maternal death. Although existing contraceptive strategies have been widely used in people's lives, there have not been satisfactory feedbacks due to low contraceptive efficacy and related side effects (e.g., decreased sexuality, menstrual cycle disorder, and even lifelong infertility). In recent years, biomaterials-based long-acting reversible contraception has received increasing attention from the viewpoint of fundamental research and practical applications mainly owing to improved delivery routes and controlled drug delivery. This review summarizes recent progress in advanced biomaterials for long-acting reversible contraception via various delivery routes, including subcutaneous implant, transdermal patch, oral administration, vaginal ring, intrauterine device, fallopian tube occlusion, vas deferens contraception, and Intravenous administration. In addition, biomaterials, especially nanomaterials, still need to be improved and prospects for the future in contraception are mentioned.

Impact of the menstrual cycle and ethinyl estradiol/etonogestrel contraceptive vaginal ring on granulysin and other mucosal immune mediators

PROBLEM

Changes in sex hormones during the menstrual cycle and contraceptive vaginal ring (CVR) use influence immunity within the female genital tract, but the magnitude of these effects and their anatomical location are unclear.

METHOD OF STUDY

In a prospective study, 29 women were assessed at three-time points: follicular phase, luteal phase, and one month after initiation of the ethinyl estradiol/etonogestrel CVR (NuvaRing®, Merck). We performed microarrays on endocervical cytobrushes and measured immune mediators in cervicovaginal fluid, adjusting for bacterial vaginosis and the presence of blood. We compared these results to public gene expression data from the fallopian tubes, endometrium, endo- and ectocervix, and vagina.

RESULTS

Immune-related gene expression in the endocervix and immune mediators in cervicovaginal fluid increased during CVR use versus both menstrual phases, and in the follicular versus luteal phase. The antimicrobial protein granulysin was high during CVR use, intermediate in the follicular phase, and nearly absent from the luteal phase. Re-analysis of public gene expression data confirmed increased immune-related gene expression in the endocervix during the follicular phase. However, in the fallopian tube, endometrium, and vagina, the follicular phase showed immunosuppression.

CONCLUSIONS

Immune-related genes in the cervicovaginal tract were highest during CVR use, intermediate in the follicular phase, and lowest in the luteal phase. Granulysin is a potential biomarker of menstrual phase: Frequently detected in follicular samples, but rare in luteal. Lastly, immunological differences between the follicular and luteal phases vary throughout the female genital tract.

Pharmacokinetics and tolerability of a novel progesterone intravaginal ring in sheep

The objectives of this work were to evaluate the in vitro release and in vivo pharmacokinetics and local tolerability of a novel, segmented ethylene-vinyl acetate (EVA) intravaginal ring (IVR) delivering progesterone (P) in drug-naïve ovariectomized female Dorset crossbred sheep. Following preparation and assessment of in vitro release of P, animals were randomized into one of six treatment groups: group 1 Crinone® 8% gel (90 mg); group 2 Prometrium® 200-mg capsules; group 3 placebo IVR; group 4 progesterone (P) IVR 4 mg/day; group 5 P IVR 8 mg/day; or group 6 P IVR 12 mg/day. Crinone 8% gel and Prometrium capsules were administered once daily for 28 days. IVRs were inserted vaginally on day 1 and remained in place through day 14; a new ring was administered on day 15 and was removed at day 28. Animals underwent daily examinations to confirm ring placement, and vaginal irritation was scored from 0 (none) to 4 (severe). Blood samples were taken at scheduled times for pharmacokinetic analysis. Postmortem examinations performed on all IVR groups included vaginal irritation, macroscopic, and microscopic evaluations, including irritation scoring and histopathology. Intravaginal rings were retained over 28 days in all animals. Clinical observations showed no significant abnormal findings in any group. Pharmacokinetic analysis in animals showed sustained release of P over from days 0 through 14 of ring use. Irritation scores and microscopic assessments were consistent with the IVRs being well tolerated. These results will guide future human clinical studies to ultimately develop an IVR for use in women for the prevention of preterm birth.

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.

Put a Ring in It: Exploring Women's Experiences with the Contraceptive Vaginal Ring in Ontario

BACKGROUND

Although the contraceptive vaginal ring (CVR) has been available in Canada since 2001, overall use and availability remain low compared with other combined hormonal contraceptive methods. We aimed to explore women's experiences with the CVR in Ontario as well as factors that influenced their decisions to choose the method and continue/discontinue use.

METHODS

We conducted a multimethod qualitative study that consisted of an anonymous online survey and in-depth telephone interviews with a subset of survey participants. We used descriptive statistics to analyze the survey data and analyzed our interviews for content and themes using both deductive and inductive techniques.

RESULTS

From May to July 2015, we received 103 survey responses and conducted 29 in-depth interviews. Many participants described positive experiences with the CVR and found it to be an especially convenient method. Women who discontinued use of the CVR cited high costs, access barriers, and negative media reports as important factors in their decision. Our participants primarily relied on their physicians for contraceptive information but did not feel fully informed about potential side effects. Several women identified the CVR as an "in between" method in the transition from oral contraceptive pills to the intrauterine device.

CONCLUSIONS

Our findings suggest that the CVR represents a convenient and desirable contraceptive option for some women. However, participants expressed a desire for health care providers to provide more comprehensive information about a full range of contraceptive methods. Improving access to a full range of low-cost contraceptives in Ontario seems to be warranted.

Treatment and prevention of HIV infection with long-acting antiretrovirals

INTRODUCTION

Current antiretroviral therapy allows to achieve and sustain maximal suppression of HIV replication in most treated patients. As result, the life expectancy of HIV-infected persons has improved dramatically and is nowadays similar to that of the HIV-negative population. However, oral antiretrovirals have to be taken daily and indefinitely to avoid resumption of HIV replication and selection of drug resistance. Unfortunately, drug adherence is often suboptimal and tends to decline over time. Areas covered: New drugs, formulations and delivery systems are being developed for extended-release of antiretrovirals. At this time, intramuscular cabotegravir and rilpivirine, dapivirine vaginal rings and tenofovir alafenamide subdermal implants are the products in more advanced stages of clinical development. Their pharmacokinetics/dynamics and safety/efficacy are reviewed. Expert commentary: In the absence of eradicative therapy for individuals with HIV infection and protective vaccines for persons at risk, long-term antiretroviral therapy is the best approach for preventing disease progression in patients and halting transmissions, either as result of 'treatment as prevention' for HIV carriers or 'pre-exposure prophylaxis' for uninfected individuals at risk. In all these scenarios, the advent of long-acting antiretrovirals will expand options for overcoming the challenge of suboptimal drug adherence and reduce the burden of HIV infection.

Pulmonary Embolism Masquerading as High Altitude Pulmonary Edema at High Altitude

Pandey, Prativa, Benu Lohani, and Holly Murphy. Pulmonary embolism masquerading as high altitude pulmonary edema at high altitude. High Alt Med Biol. 17:353-358, 2016.-Pulmonary embolism (PE) at high altitude is a rare entity that can masquerade as or occur in conjunction with high altitude pulmonary edema (HAPE) and can complicate the diagnosis and management. When HAPE cases do not improve rapidly with descent, other diagnoses, including PE, ought to be considered. From 2013 to 2015, we identified eight cases of PE among 303 patients with initial diagnosis of HAPE. Upon further evaluation, five had deep vein thrombosis (DVT). One woman had a contraceptive ring and seven patients had no known thrombotic risks. PE can coexist with or mimic HAPE and should be considered in patients presenting with shortness of breath from high altitude regardless of thrombotic risk.

Porphyria cutanea tarda associated with HFE C282Y homozygosity, iron overload, and use of a contraceptive vaginal ring

Porphyria cutanea tarda (PCT) is characterized by decreased uroporphyrinogen decarboxylase activity in hepatocytes, uroporphyrin I and heptacarboxyl porphyrin III accumulation, photosensitivity dermatitis, and increased storage iron. In women, estrogen therapy, including oral contraceptives, postmenopausal hormone replacement, and tamoxifen for breast cancer treatment, is a risk factor for PCT. We report the case of a woman who presented with PCT, HFE C282Y homozygosity, and hepatic iron overload and was using a contraceptive vaginal ring containing ethinyl estradiol, an estrogen. We discuss this case in the context of characteristics of other persons with PCT, including common HFE mutations, iron overload, and estrogen exposure.