Systemic hormonal contraception and risk of venous thromboembolism

Tailoring drug release from long-acting contraceptive levonorgestrel intrauterine systems

The wide array of polydimethylsiloxane (PDMS) variants available on the market, coupled with the intricate combination of additives in silicone polymers, and the incomplete understanding of drug release behavior make formulation development of levonorgestrel intrauterine systems (LNG-IUSs) formidable. Accordingly, the objectives of this work were to investigate the impact of excipients on formulation attributes and in vitro performance of LNG-IUSs, elucidate drug release mechanisms, and thereby improve product understanding. LNG-IUSs with a wide range of additives and fillers were prepared, and in vitro drug release testing was conducted for up to 12 months. Incorporating various additives and/or fillers (silica, silicone resins, silicone oil, PEG, etc.) altered the crystallization kinetics of the crosslinked polymer, the viscosity, and the microstructure. In addition, drug-excipient interactions can occur. Interestingly, additives which increased matrix hydrophobicity and hindered PDMS crystallization facilitated dissolution and permeation of the lipophilic LNG. The influence of additives and lubricants on the mechanical properties of LNG-IUSs were also evaluated. PDMS chemical substitution and molecular weight were deemed to be most critical polymer attributes to the in vitro performance of LNG-IUSs. Drugs with varying physicochemical characteristics were used to prepare IUSs, modeling of the release kinetics was performed, and correlations between release properties and the various physicochemical attributes of the model drugs were established. Strong correlations between first order release rate constants and both drug solubility and Log P underpin the partition and diffusion-based release mechanisms in LNG-IUSs. This is the first comprehensive report to provide a mechanistic understanding of material-property-performance relationships for IUSs. This work offers an evidence-based approach to rational excipient selection and tailoring of drug release to achieve target daily release rates in vivo. The novel insights gained through this research could be helpful for supporting development of brand and generic IUS products as well as their regulatory assessment.

Experts' view on the role of oestrogens in combined oral contraceptives: emphasis on oestetrol (E4)

Introduction

The evolution of contraception has been crucial for public health and reproductive well-being. Over the past 60 years, combined oral contraceptives (COCs) have remained an important part of the contraceptive landscape worldwide; continued development has worked toward maintaining efficacy and improving safety.

Methods

Seven global experts convened to discuss the clinical relevance of the oestrogen in COCs, focusing on the impact of the new oestrogen, oestetrol (E4). Participants then commented through an online forum on the summary content and other participants' feedback. We prepared this report to describe the experts' views, their follow-up from the open forum and the evidence supporting their views.

Results

Ethinylestradiol (EE) and oestradiol (E2) affect receptors similarly whereas E4 has differential effects, especially in the liver and breast. Adequate oestrogen doses in COCs ensure regular bleeding and user acceptability. EE and E4 have longer half-lives than E2; accordingly, COCs with EE and E4 offer more predictable bleeding than those with E2. Oestrogen type and progestin influence VTE risk; E2 poses a lower risk than EE; although promising, E4/DRSP VTE risk is lacking population-based data. COCs alleviate menstrual symptoms, impact mental health, cognition, libido, skin, and bone health.

Conclusion

Oestrogens play an important role in the contraceptive efficacy, bleeding patterns, and overall tolerability/safety of COCs. Recent studies exploring E4 combined with DRSP show promising results compared to traditional formulations, but more definitive conclusions await further research.

Towards comprehensive management of symptomatic endometriosis: beyond the dichotomy of medical versus surgical treatment

Except when surgery is the only option because of organ damage, the presence of suspicious lesions, or the desire to conceive, women with endometriosis-associated pain often face a choice between medical and surgical treatment. In theory, the description of the potential benefits and potential harms of the two alternatives should be standardized, unbiased, and based on strong evidence, enabling the patient to make an informed decision. However, doctor's opinion, intellectual competing interests, local availability of specific services and (mis)information obtained from social media, and online support groups can influence the type of advice given and affect patients' choices. This is compounded by the paucity of robust data from randomized controlled trials, and the anxiety of distressed women who are eager to do anything to alleviate their disabling symptoms. Vulnerable patients are more likely to accept the suggestions of their healthcare provider, which can lead to unbalanced and physician-centred decisions, whether in favour of either medical or surgical treatment. In general, treatments should be symptom-orientated rather than lesion-orientated. Medical and surgical modalities appear to be similarly effective in reducing pain symptoms, with medications generally more successful for severe dysmenorrhoea and surgery more successful for severe deep dyspareunia caused by fibrotic lesions infiltrating the posterior compartment. Oestrogen-progestogen combinations and progestogen monotherapies are generally safe and well tolerated, provided there are no major contraindications. About three-quarters of patients with superficial peritoneal and ovarian endometriosis and two-thirds of those with infiltrating fibrotic lesions are ultimately satisfied with their medical treatment although the remainder may experience side effects, which may result in non-compliance. Surgery for superficial and ovarian endometriosis is usually safe. When fibrotic infiltrating lesions are present, morbidity varies greatly depending on the skill of the individual surgeon, the need for advanced procedures, such as bowel resection and ureteral reimplantation, and the availability of expert colorectal surgeons and urologists working together in a multidisciplinary approach. The generalizability of published results is adequate for medical treatment but very limited for surgery. Moreover, on the one hand, hormonal drugs induce disease remission but do not cure endometriosis, and symptom relapse is expected when the drugs are discontinued; on the other hand, the same drugs should be used after lesion excision, which also does not cure endometriosis, to prevent an overall cumulative symptom and lesion recurrence rate of 10% per postoperative year. Therefore, the real choice may not be between medical treatment and surgery, but between medical treatment alone and surgery plus postoperative medical treatment. The experience of pain in women with endometriosis is a complex phenomenon that is not exclusively based on nociception, although the role of peripheral and central sensitization is not fully understood. In addition, trauma, and especially sexual trauma, and pelvic floor disorders can cause or contribute to symptoms in many individuals with chronic pelvic pain, and healthcare providers should never take for granted that diagnosed or suspected endometriosis is always the real, or the sole, origin of the referred complaints. Alternative treatment modalities are available that can help address most of the additional causes contributing to symptoms. Pain management in women with endometriosis may be more than a choice between medical and surgical treatment and may require comprehensive care by a multidisciplinary team including psychologists, sexologists, physiotherapists, dieticians, and pain therapists. An often missing factor in successful treatment is empathy on the part of healthcare providers. Being heard and understood, receiving simple and clear explanations and honest communication about uncertainties, being invited to share medical decisions after receiving detailed and impartial information, and being reassured that a team member will be available should a major problem arise, can greatly increase trust in doctors and transform a lonely and frustrating experience into a guided and supported journey, during which coping with this chronic disease is gradually learned and eventually accepted. Within this broader scenario, patient-centred medicine is the priority, and whether or when to resort to surgery or choose the medical option remains the prerogative of each individual woman.

Exploring the potential for a set of UK hormone replacement therapy eligibility guidelines: A suggested proposal on the topic of venous thromboembolism

OBJECTIVE

To explore the feasibility for a set of hormone replacement therapy (HRT) eligibility guidelines that follow a similar structure and appearance to the UKMEC guidance for contraception. To enable non-specialists to feel confident in safely prescribing HRT and to aid selection of the most appropriate first line treatment.

METHODS

A literature review was undertaken with evidence summarised on the topic of venous thromboembolism (VTE) which is an area frequently considered a barrier to prescribing. Medical eligibility tables which separated HRT by type were then produced for a set of VTE-related topics.

RESULTS

The literature search confirmed the importance of distinguishing between different types and routes of administration when considering the suitability of HRT. Much of the evidence has been based on older synthetic types of HRT and whilst they still have a role in management, these medications carry different risks to the now more accepted use of body identical types. The search also highlighted the nuances involved, increasing the complexity of forming guidelines, with the need for consideration to be given to an individual's own perception of risks and benefits.

CONCLUSION

The demand for HRT has risen in recent years and there is a need for this to be managed effectively, particularly for patients in primary care. The production of this type of guidance will enable the non-specialist to feel confident in safe and evidence-based prescribing. The guidelines are also designed to demonstrate to prescribers which complex patients should be referred onto menopause specialists.

Gestodene causes masculinization of the western mosquitofish (Gambusia affinis): Insights from ovary metabolomics

Gestodene (GES) is a common synthetic progesterone frequently detected in aquatic environments. Chronic exposure to GES can cause masculinization of a variety of fish; however, whether metabolism is closely related to the masculinization has yet to be explored. Hence, the ovary metabolome of adult female western mosquitofish (Gambusia affinis) after exposing to GES (0.0, 5.0, 50.0, and 500.0 ng/L) for 40 days was analyzed by using high-performance liquid chromatography ionization with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS). The results showed that GES increased the levels of cysteine, taurine, ophthalmic acid and cAMP while decreased methionine, these metabolites changes may owing to the oxidative stress of the ovaries; while taurcholic acid and uric acid were decreased along with induced oocyte apopotosis. Steroids hormone metabolism was also significantly affected, with progesterone and cortisol being the most affected. Enzyme-linked immunoassay results showed that estradiol levels were decreased while testosterone levels were increased with GES exposure. In addition, correlation analysis showed that the differential metabolites of some amino acids (e.g. leucine) were strongly correlated with the levels of steroids hormones secreted by the pituitary gland. The results of this study suggest that GES affects ovarian metabolism via the hypothalamus-pituitary-gonad and hypothalamic-pituitary-adrenal axes, impair antioxidant capacity, induce apoptosis in the ovary of G. affinis, and finally caused masculinization.

Comparison of estrogenic components used for hormonal contraception

Attempts have been made over the years to replace ethinyl estradiol (EE) in combined oral contraceptives (COCs) with the less potent natural estrogen estradiol (E2), or its prodrug, E2 valerate (E2V), to improve their safety and tolerability. Recently, a COC incorporating a novel weak natural estrogen, estetrol (E4), combined with drospirenone, has become available. We present a comparative analysis of the three prevailing estrogens used in COCs, focusing on their structure-function relationships, receptor-binding affinity, potency, metabolism, pharmacokinetic parameters, and pharmacodynamics. The binding affinity of EE to estrogen receptor (ER)α is twice that of E2, whereas its affinity for ERβ is about one-half that of E2. E4 has a lower binding affinity for the ERs than E2. The high potency of EE is notable in its dramatic increase in estrogen-sensitive hepatic globulins and coagulation factors. EE and E2 undergo extensive and comparable metabolism, while E4 produces only a very limited number of metabolites. E4 has the highest bioavailability among the three estrogens, with E2 having <5%. Studies demonstrate consistent ovulation inhibition, although a higher dose of E4 (15 mg) in COCs is required to achieve follicular suppression compared to E2 (1-3 mg) and EE (0.01-0.035 mg). E2 and E4 in COCs may be less stimulatory of coagulant proteins than EE. Studies with E2/dienogest suggest a comparable risk of venous thromboembolism to EE/levonorgestrel, while data assessing risk with an E4-based COC are insufficient. Nevertheless, the E4-based formulation shows promise as a potential alternative to EE and E2 due to its lower potency and possibly fewer side effects.

Metformin and Combined Oral Contraceptive Pills in the Management of Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis

CONTEXT

Polycystic ovary syndrome (PCOS) affects more than 1 in 10 women.

OBJECTIVE

As part of the 2023 International PCOS Guidelines update, comparisons between combined oral contraceptive pills (COCP), metformin, and combination treatment were evaluated.

DATA SOURCES

Ovid Medline, Embase, PsycINFO, All EBM, and CINAHL were searched.

STUDY SELECTION

Women with PCOS included in randomized controlled trials (RCTs).

DATA EXTRACTION

We calculated mean differences and 95% CIs regarding anthropometrics, metabolic, and hyperandrogenic outcomes. Meta-analyses and quality assessment using GRADE were performed.

DATA SYNTHESIS

The search identified 1660 publications; 36 RCTs were included. For hirsutism, no differences were seen when comparing metformin vs COCP, nor when comparing COCP vs combination treatment with metformin and COCP. Metformin was inferior on free androgen index (FAI) (7.08; 95% CI 4.81, 9.36), sex hormone binding globulin (SHBG) (-118.61 nmol/L; 95% CI -174.46, -62.75) and testosterone (0.48 nmol/L; 95% CI 0.32, 0.64) compared with COCP. COCP was inferior for FAI (0.58; 95% CI 0.36, 0.80) and SHBG (-16.61 nmol/L; 95% CI -28.51, -4.71) compared with combination treatment, whereas testosterone did not differ. Metformin lowered insulin (-27.12 pmol/L; 95% CI -40.65, -13.59) and triglycerides (-0.15 mmol/L; 95% CI -0.29, -0.01) compared with COCP. COCP was inferior for insulin (17.03 pmol/L; 95% CI 7.79, 26.26) and insulin resistance (0.44; 95% CI 0.17, 0.70) compared with combination treatment.

CONCLUSIONS

The choice of metformin or COCP treatment should be based on symptoms, noting some biochemical benefits from combination treatment targeting both major endocrine disturbances seen in PCOS (hyperinsulinemia and hyperandrogenism).

Proposal for targeted, neo-evolutionary-oriented secondary prevention of early-onset endometriosis and adenomyosis. Part II: medical interventions

According to consistent epidemiological data, the slope of the incidence curve of endometriosis rises rapidly and sharply around the age of 25 years. The delay in diagnosis is generally reported to be between 5 and 8 years in adult women, but it appears to be over 10 years in adolescents. If this is true, the actual onset of endometriosis in many young women would be chronologically placed in the early postmenarchal years. Ovulation and menstruation are inflammatory events that, when occurring repeatedly for years, may theoretically favour the early development of endometriosis and adenomyosis. Moreover, repeated acute dysmenorrhoea episodes after menarche may not only be an indicator of ensuing endometriosis or adenomyosis, but may also promote the transition from acute to chronic pelvic pain through central sensitization mechanisms, as well as the onset of chronic overlapping pain conditions. Therefore, secondary prevention aimed at reducing suffering, limiting lesion progression, and preserving future reproductive potential should be focused on the age group that could benefit most from the intervention, i.e. severely symptomatic adolescents. Early-onset endometriosis and adenomyosis should be promptly suspected even when physical and ultrasound findings are negative, and long-term ovulatory suppression may be established until conception seeking. As nowadays this could mean using hormonal therapies for several years, drug safety evaluation is crucial. In adolescents without recognized major contraindications to oestrogens, the use of very low-dose combined oral contraceptives is associated with a marginal increase in the individual absolute risk of thromboembolic events. Oral contraceptives containing oestradiol instead of ethinyl oestradiol may further limit such risk. Oral, subcutaneous, and intramuscular progestogens do not increase the thromboembolic risk, but may interfere with attainment of peak bone mass in young women. Levonorgestrel-releasing intra-uterine devices may be a safe alternative for adolescents, as amenorrhoea is frequently induced without suppression of the ovarian activity. With regard to oncological risk, the net effect of long-term oestrogen-progestogen combinations use is a small reduction in overall cancer risk. Whether surgery should be considered the first-line approach in young women with chronic pelvic pain symptoms seems questionable. Especially when large endometriomas or infiltrating lesions are not detected at pelvic imaging, laparoscopy should be reserved to adolescents who refuse hormonal treatments or in whom first-line medications are not effective, not tolerated, or contraindicated. Diagnostic and therapeutic algorithms, including self-reported outcome measures, for young individuals with a clinical suspicion of early-onset endometriosis or adenomyosis are proposed.

Polycystic ovary syndrome: pathophysiology and therapeutic opportunities

Polycystic ovary syndrome is characterised by excessive levels of androgens and ovulatory dysfunction, and is a common endocrine disorder in women of reproductive age. Polycystic ovary syndrome arises as a result of polygenic susceptibility in combination with environmental influences that might include epigenetic alterations and in utero programming. In addition to the well recognised clinical manifestations of hyperandrogenism and ovulatory dysfunction, women with polycystic ovary syndrome have an increased risk of adverse mental health outcomes, pregnancy complications, and cardiometabolic disease. Unlicensed treatments have limited efficacy, mostly because drug development has been hampered by an incomplete understanding of the underlying pathophysiological processes. Advances in genetics, metabolomics, and adipocyte biology have improved our understanding of key changes in neuroendocrine, enteroendocrine, and steroidogenic pathways, including increased gonadotrophin releasing hormone pulsatility, androgen excess, insulin resistance, and changes in the gut microbiome. Many patients with polycystic ovary syndrome have high levels of 11-oxygenated androgens, with high androgenic potency, that might mediate metabolic risk. These advances have prompted the development of new treatments, including those that target the neurokinin-kisspeptin axis upstream of gonadotrophin releasing hormone, with the potential to lessen adverse clinical sequelae and improve patient outcomes.

Drospirenone and estetrol: evaluation of a newly approved novel oral contraceptive

INTRODUCTION

Estetrol (E4) is a native estrogen produced only by the fetal liver during pregnancy. E4 is the first new estrogen to be used in hormonal contraception since the introduction of oral contraceptives in 1960. Ethinyl estradiol, the most commonly used estrogen in oral contraceptives today, increases the risks of thromboembolism and has other significant hepatic impacts, which induce important drug-drug interactions. On the other hand, Phase 2 E4 characterization studies demonstrated that E4 has negligible impacts on liver, breast, and vascular endothelium due to its distinct tissue selectivity. Combined with drospirenone (DRSP), E4 offers an improved safety profile for oral contraception.

AREAS COVERED

This paper briefly highlights the unique pharmacokinetic and pharmacodynamic features of E4. The efficacy, safety, and tolerability results from the Phase 2 and 3 studies of the E4/DRSP pill are discussed to provide the reader with a thorough understanding of E4 and information to use when counseling potential users.

EXPERT OPINION

The estetrol/drospirenone oral contraceptive is effective and well tolerated and provides good cycle control. In the future, estetrol may be the estrogen of choice if subsequent evidence verifies that it reduces the risks associated with current estrogens, such as venous thromboembolism and drug-drug interactions.

Combined oral contraceptive pill compared with no medical treatment in the management of polycystic ovary syndrome: A systematic review

OBJECTIVE

As part of the update of the International Evidence-Based Guidelines for the Assessment and Management of polycystic ovary syndrome (PCOS), a systematic review was performed to inform evidence-based recommendations.

DESIGN

Systematic review. Only randomised controlled trial were included.

PATIENTS

Women with PCOS; the use of combined oral contraceptive pills (COCP) was compared with no medical treatment.

MEASUREMENTS

Outcomes were designed in collaboration with clinical experts, researchers, and consumers. Critical outcomes included hirsutism, irregular cycles, quality of life, body mass index (BMI), and weight.

RESULTS

1660 publications were identified, but only four studies were included. No studies could be combined for meta-analysis. COCP treatment improved cycle regularity compared with no medical treatment (100% vs. 0%, with low certainty of evidence). COCP showed no difference in improvement of hirsutism or BMI compared with placebo or lifestyle; a lower weight after COCP compared with no treatment (mean difference [MD] -8.0 (95% confidence interval, CI -11.67); -4.33 kg); and improvement in quality of life (MD 1.2 [95% CI 0.96]; 1.44), but these results were all very low certainty of evidence.

CONCLUSION

Results show that COCP benefit cycle regulation, but other benefits or potential adverse effects were only identified with very low certainty of evidence. The COCP is frontline medical treatment in PCOS, but this is still based on established efficacy in the broader general population. Our results show that research in PCOS is seriously lacking and should be prioritised to capture core reproductive, metabolic and psychological outcomes important in PCOS.

[The Thromboembolism Risk with Combined Hormonal Contraceptives: Current Status and Prescribing Practice]

The Thromboembolism Risk with Combined Hormonal Contraceptives: Current Status and Prescribing Practice Abstract. The use of combined hormonal contraceptives (CHC) increases not only the risk for venous thromboembolism, but also for arterial thromboembolism. The risk for thromboembolism is the same for non-oral CHC (patches, vaginal rings) as for oral CHC. Risk factors such as age >35, obesity, smoking and a positive family history need to be recognized and considered in contraceptive counselling. Elaborate information concerning risks and benefits is mandatory. This applies to first-time as well as long-term users. Careful investigation of the history is required, and the risk factors need to be re-evaluated at yearly prescription. It is also very important to inform the patients about the early symptoms of thrombosis or pulmonary embolism, so that therapy can be started immediately. Apart from these risks, CHC may have beneficial effects on organs such as the ovaries, the endometrium and the general well-being for many women. When prescribing a CHC for the first time or when changing to another preparation, one should always weigh up whether certain benefits justify prescribing a preparation with a slightly higher risk of thrombosis compared to the second-generation pill or preparations with Estradiol/Nomegestrolacetat. Women who are already using a third-generation pill or a pill with drospirenone or cyproterone acetate and feel comfortable with it do not need to switch to another preparation (provided no new risk factors have arisen). For women with increased risks, i.e. several relative contraindications or one absolute contraindication, safe alternatives to CHC include progestogen-only preparations, intrauterine devices containing copper or levonorgestrel or, after family planning has been completed, surgical methods (sterilisation/vasectomy).

Ethinylestradiol in combined hormonal contraceptive has a broader effect on serum proteome compared with estradiol valerate: a randomized controlled trial

STUDY QUESTION

Does an estradiol-based combined oral contraceptive (COC) have a milder effect on the serum proteome than an ethinylestradiol (EE)-based COC or dienogest (DNG) only?

SUMMARY ANSWER

The changes in serum proteome were multifold after the use of a synthetic EE-based COC compared to natural estrogen COC or progestin-only preparation.

WHAT IS KNOWN ALREADY

EE-based COCs widely affect metabolism, inflammation, hepatic protein synthesis and blood coagulation. Studies comparing serum proteomes after the use of COCs containing EE and natural estrogens are lacking.

STUDY DESIGN, SIZE, DURATION

This was a spin-off from a randomized, controlled, two-center clinical trial. Women (n = 59) were randomized to use either EE + DNG, estradiol valerate (EV) + DNG or DNG only continuously for 9 weeks.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were healthy, young, white volunteer women. Serum samples were collected before and after 9 weeks of hormonal exposure. Samples from 44 women were available for analysis (EE + DNG n = 14, EV + DNG n = 16 and DNG only n = 14). Serum proteins were analyzed by quantitative, discovery-type label-free proteomics.

MAIN RESULTS AND THE ROLE OF CHANCE

Altogether, 446 proteins/protein families with two or more unique peptides were detected and quantified. The number of proteins/families that altered over the 9-week period within the study groups was 121 for EE + DNG and 5 for EV + DNG, while no changes were detected for DNG only. When alterations were compared between the groups, significant differences were detected for 63 proteins/protein families, of which 58 were between the EE + DNG and EV + DNG groups. The most affected functions during the use of EE + DNG were the complement system, acute phase response signaling, metabolism and the coagulation system. The results were validated by fetuin-B and cortisol-binding globulin ELISA and sex hormone-binding globulin immunoassay.

LARGE SCALE DATA

Data are available via ProteomeXchange with identifiers PXD033617 (low abundance fraction) and PXD033618 (high abundance fraction).

LIMITATIONS, REASONS FOR CAUTION

The power analysis of the trial was not based on the proteomic analysis of this spin-off study. In the future, targeted proteomic analysis with samples from another trial should be carried out in order to confirm the results.

WIDER IMPLICATIONS OF THE FINDINGS

The EE-based COC exerted a broader effect on the serum proteome than the EV-based COC or the DNG-only preparation. These results demonstrate that the effects of EE in COCs go far beyond the established endpoint markers of estrogen action, while the EV combination is closer to the progestin-only preparation. The study indicates that EV could provide a preferable option to EE in COCs in the future and signals a need for further studies comparing the clinical health outcomes of COCs containing EE and natural estrogens.

STUDY FUNDING/COMPETING INTEREST(S)

Funding for this researcher-initiated study was obtained from the Helsinki University Hospital research funds, the Hospital District of Helsinki and Uusimaa, the Sigrid Juselius Foundation, the Academy of Finland, the Finnish Medical Association, the University of Oulu Graduate School, the Emil Aaltonen Foundation, the Swedish Cultural Foundation in Finland, the Novo Nordisk Foundation, Orion Research Foundation and the Northern Ostrobothnia Regional Fund. The funders had no role in study design, data collection and analysis, publishing decisions or manuscript preparation. T.P. has received honoraria for lectures, consultations and research grants from Exeltis, Gedeon Richter, MSD, Merck, Pfizer, Roche, Stragen and Mithra Pharmaceuticals. O.H. occasionally serves on advisory boards for Bayer AG and Gedeon Richter and has designed and lectured at educational events for these companies. The other authors have nothing to disclose. O.H. occasionally serves on advisory boards for Bayer AG and Gedeon Richter and has designed and lectured at educational events for these companies. The other authors have nothing to disclose.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT02352090.

TRIAL REGISTRATION DATE

27 January 2015.

DATE OF FIRST PATIENT’S ENROLMENT

1 April 2015.

Combined oral contraceptives containing estradiol valerate vs ethinylestradiol on coagulation: A randomized clinical trial

INTRODUCTION

Contraceptives containing ethinylestradiol (EE) induce changes in the coagulation system and are associated with a risk of venous thromboembolism. However, studies comparing the effects of combined oral contraceptives containing EE and low-potency estrogens (ie, estradiol [E₂ ] and estradiol valerate [EV]) on coagulation biomarkers are limited. This study represents secondary outcomes of a randomized trial comparing combined oral contraceptives containing EV + dienogest (DNG), EE + DNG, and DNG alone on selected coagulation biomarkers. We could compare the specific effects of the different estrogen components owing to the inclusion of preparations containing the same progestin.

MATERIAL AND METHODS

We enrolled 59 healthy, 18- to 35-year-old, non-smoking women, of whom three discontinued. The participants were randomly allocated to 9 weeks of continuous treatment with EV 2 mg + DNG 2-3 mg (n = 20), EE 0.03 mg + DNG 2 mg (n = 20), or DNG 2 mg (n = 19). Blood samples were collected at baseline and after 9 weeks. We assessed coagulation in vitro by thrombin generation using the Calibrated Automated Thrombogram. Thrombin generation was evaluated by lag time, time to thrombin peak, thrombin peak, and endogenous thrombin potential in response to tissue factor (1 pm). In vivo coagulation assessment was based on levels of prothrombin fragment 1 + 2 (F1 + 2) (thrombin generation) and D-dimer (fibrin turnover).

CLINICAL TRIAL REGISTRATION

NCT02352090.

RESULTS

Lag time and time to thrombin peak remained unaltered after exposure to EV + DNG, whereas EE + DNG shortened both lag time (mean percentage change -24%, 95% confidence interval [CI] -32% to -15%; p < 0.01) and time to thrombin peak (-26%, 95% CI -37% to -16%; p < 0.01). EV + DNG induced lower thrombin peak and endogenous thrombin potential than EE + DNG (peak; +45%, 95% CI 22%-67% vs +147%,95% CI 96%-198%; p < 0.01, and endogenous thrombin potential; +26%, 95% CI 15%-38% vs +64%, 95% CI 51%-76%; p < 0.01). Median F1 + 2 levels remained unchanged with EV + DNG (p = 0.22) but increased within normal ranges with EE + DNG (from 152 pmol/L, 95% CI 127-206] pmol/L to 194 pmol/L, 95% CI 149-250 pmol/L, p = 0.04). The within-group change in D-dimer levels was not significant in any of the groups. DNG alone did not affect these biomarkers.

CONCLUSIONS

Both in vitro and in vivo thrombin generation was lower after exposure to EV + DNG compared with EE + DNG. The lower thrombin generation measures after treatment with EV + DNG indicate less enhancement of coagulation potential and suggest that EV may be favorable to EE as a component of combined oral contraceptives.