Evaluation of a new estradiol oral contraceptive: estradiol valerate and dienogest

Hormonal contraceptive exposure relates to changes in resting state functional connectivity of anterior cingulate cortex and amygdala

Introduction

Hormonal contraceptives (HCs), nowadays one of the most used contraceptive methods, downregulate endogenous ovarian hormones, which have multiple plastic effects in the adult brain. HCs usually contain a synthetic estrogen, ethinyl-estradiol, and a synthetic progestin, which can be classified as androgenic or anti-androgenic, depending on their interaction with androgen receptors. Both the anterior cingulate cortex (ACC) and the amygdala express steroid receptors and have shown differential functionality depending on the hormonal status of the participant and the use of HC. In this work, we investigated for the first time the relationship between ACC and amygdala resting state functional connectivity (rs-FC) and HC use duration, while controlling for progestin androgenicity.

Methods

A total of 231 healthy young women participated in five different magnetic resonance imaging studies and were included in the final analysis. The relation between HC use duration and (i) gray matter volume, (ii) fractional amplitude of low-frequency fluctuations, and (iii) seed-based connectivity during resting state in the amygdalae and ACC was investigated in this large sample of women.

Results

In general, rs-FC of the amygdalae with frontal areas, and between the ACC and temporoparietal areas, decreased the longer the HC exposure and independently of the progestin's androgenicity. The type of HC's progestin did show a differential effect in the gray matter volume of left ACC and the connectivity between bilateral ACC and the right inferior frontal gyrus.

Hormonal therapies and venous thrombosis: Considerations for prevention and management

Background

Venous thromboses are well‐established complications of hormonal therapy. Thrombosis risk is seen with both hormonal contraceptive agents and with hormone replacement therapy for menopause and gender transition. Over the past several decades, large epidemiological studies have helped better define these risks.

Objectives

To review and discuss the differences in thrombosis risk of the many of hormonal preparations available as well as their interaction with patient‐specific factors.

Methods

We conducted a narrative review of the available literature regarding venous thrombosis and hormonal therapies including for contraception, menopausal symptoms, and gender transition.

Results

Thrombosis risk with estrogen‐containing compounds increases with increasing systemic dose of estrogen. While progesterone‐only–containing products are not associated with thrombosis, when paired with estrogen in combined oral contraceptives, the formulation of progesterone does impact the risk. These components, along with patient‐specific factors, may influence the choice of hormonal preparation. For patients who develop thrombosis on hormonal treatment, anticoagulation is protective against future thrombosis. Duration of anticoagulation is dependent on ongoing and future hormone therapy choice. Finally, the optimal management of hormone therapy for individuals diagnosed with prothrombotic illnesses such as COVID‐19 remains unclear.

Conclusions

When contemplating hormonal contraception or hormone replacement therapy, clinicians must consider a variety of factors including hormone type, dose, route, personal and family history of thrombosis, and other prothrombotic risk factors to make informed, personalized decisions regarding the risk of venous thrombosis.

Hormonal Contraception: Systemic Estrogen and Progestin Preparations

Combined hormonal contraception (CHC) are short-acting, reversible methods containing both estrogen and progestin. Available CHC methods include combined oral contraceptives, transdermal patches, and vaginal rings. The combined oral contraceptive remains the most commonly used contraceptive method in the United States. The general principles of CHC will be reviewed, including mechanism of action and effectiveness. Unless otherwise stated, these principles apply to all CHCs. When discussing clinical studies and specific considerations related only to pills, patches, or rings, the method(s) will be specified. Words that specify sex are used when discussing studies in which sex was specified.

Clinical pharmacology of progestins

INTRODUCTION

In this paper, we report general pharmacological profile and major biological activities of natural progesterone (P) and progestins. The aim of this article consists of synthesizing the principal aspects of pharmacology and metabolism of P and progestins related to the clinical consequences of their use.

METHODS

We review scientific literature on the topic "Progestins", evaluating the most relevant data from original articles, reviews and meta-analyses.

EVIDENCE SYNTHESIS

Progestins represent a specific class of synthetic analogues of P clinically employed (alone or associated with estrogens) to manage several gynaecological conditions, for instance multiple abortions, luteal phase defect, premenstrual syndrome, abnormal uterine bleeding, endometriosis and menopause (for hormone replacement therapy). Besides their use in the field of contraception, many non-contraceptive benefits of estroprogestins are mostly due to the activities of progestins. Pharmacological characteristics, dosage and individual metabolism could be listed among the principal aspects influencing their clinical effects.

CONCLUSIONS

The choice of each progestin according to its pharmacological profile is crucial for the appropriate management of any gynaecological condition. An aware knowledge of these compounds is fundamental to hone medical practice.

Hormonal replacement therapy in adolescents and young women with chemo- or radio-induced premature ovarian insufficiency: Practical recommendations

In women with premature ovarian insufficiency (POI), hormonal therapy (HT) is indicated to decrease the risk of morbidity and to treat symptoms related to prolonged hypoestrogenism. While general recommendations for the management of HT in adults with POI have been published, no systematic suggestions focused on girls, adolescents and young women with POI following gonadotoxic treatments (chemotherapy, radiotherapy, stem cell transplantation) administered for pediatric cancer are available. In order to highlight the challenging issues specifically involving this cohort of patients and to provide clinicians with the proposal of practical therapeutic protocol, we revised the available literature in the light of the shared experience of a multidisciplinary team of pediatric oncologists, gynecologists and endocrinologists. We hereby present the proposals of a practical scheme to induce puberty in prepubertal girls and a decisional algorithm that should guide the clinician in approaching HT in post-pubertal adolescents and young women with iatrogenic POI.

Diagnosis and Management of Heavy Menstrual Bleeding and Bleeding Disorders in Adolescents

IMPORTANCE

Heavy menstrual bleeding is a common cause of anemia and reduced quality of life in adolescents. There is a higher prevalence of bleeding disorders in girls with heavy menstrual bleeding than in the general population. Pediatricians should be comfortable with the initial evaluation of heavy menstrual bleeding and the indications for referral to subspecialty care.

OBSERVATIONS

The most common cause of heavy menstrual bleeding in adolescents is ovulatory dysfunction, followed by coagulopathies. The most common inherited bleeding disorder is von Willebrand disease, and its incidence in adolescents with heavy menstrual bleeding is high. Distinguishing the etiology of heavy menstrual bleeding will guide treatment, which can include hemostatic medications, hormonal agents, or a combination of both. Among hormonal agents, the 52-mg levonogestrel intrauterine device has been shown to be superior in its effect on heavy menstrual bleeding and is safe and effective in adolescents with bleeding disorders.

CONCLUSIONS AND RELEVANCE

Anemia, need for transfusion of blood products, and hospitalization may be avoided with prompt recognition, diagnosis, and treatment of heavy menstrual bleeding, especially when in the setting of bleeding disorders. Safe and effective treatment methods are available and can greatly improve quality of life for affected adolescents. A multidisciplinary approach to the treatment of girls with bleeding disorders and history of heavy menstrual bleeding is optimal.

No. 329-Canadian Contraception Consensus Part 4 of 4 Chapter 9: Combined Hormonal Contraception

OBJECTIVE

To provide guidelines for health care providers on the use of contraceptive methods to prevent pregnancy and on the promotion of healthy sexuality.

OUTCOMES

Overall efficacy of cited contraceptive methods, assessing reduction in pregnancy rate, safety, and side effects; the effect of cited contraceptive methods on sexual health and general well-being; and the availability of cited contraceptive methods in Canada.

EVIDENCE

Medline and the Cochrane Database were searched for articles in English on subjects related to contraception, sexuality, and sexual health from January 1994 to December 2015 in order to update the Canadian Contraception Consensus published February-April 2004. Relevant Canadian government publications and position papers from appropriate health and family planning organizations were also reviewed.

VALUES

The quality of the evidence is rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice are ranked according to the method described in this report.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Knowledge and attitudes of Latin American gynecologists regarding unplanned pregnancy and use of combined oral contraceptives

Background

Unintended pregnancy is a public health problem and unmet medical need worldwide. It is estimated that in the year 2012, almost 213 million pregnancies occurred, and the global pregnancy rate decreased only slightly from 2008 to 2012. It was also estimated that 85 million pregnancies (40% of all pregnancies) were unintended and that 38% ended in an unintended birth.

Objectives

To assess knowledge and attitudes of Latin American (LA) obstetricians and gynecologists (OBGYNs) regarding unintended pregnancies and aspects of combined oral contraceptive (COC) use.

Methods

A survey was conducted during a scientific meeting about contraception in 2014, in which OBGYNs from 12 LA countries who provide attention in contraception were invited to respond to a multiple-choice questionnaire to assess their knowledge and attitudes regarding unplanned pregnancy and some aspects regarding COC use.

Results

A total of 210 OBGYNs participated in the study. Their knowledge regarding COC failure was low. The participants reported they believed that their patients habitually forgot to take a pill and that their patients did not know what to do in these situations. They were aware of the benefits of COC use; however, they were less prone to prescribe COCs for the purpose of protecting against ovarian and endometrial cancer, and one-quarter of them had doubts about the association between COC use and cancer risk.

Conclusion

The interviewed LA OBGYNs showed some flaws in terms of knowledge of COC failure rates and the non-contraceptive benefits and risks of COCs. To adequately counsel their patients regarding COC intake, OBGYNs must be updated regarding all aspects of COC use.

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.

Nomegestrol acetate-17b-estradiol for oral contraception

Oral contraceptives remain a popular method of contraception over 50 years after their introduction. While safe and effective for many women, the failure rate of oral contraception is about 8%. Concerns about the risk of venous thromboembolism continue to drive the search for the safest oral contraceptive formulations. The oral contraceptive NOMAC-E2 contains nomegestrol acetate (NOMAC) 2.5 mg + 17b-estradiol (E2) 1.5 mg. The approved dosing regimen is 24 days of active hormone, followed by a 4-day hormone-free interval. NOMAC is a progestin derived from testosterone, which has high bioavailability, rapid absorption, and a long half-life. Estradiol, though it has a lower bioavailability, has been successfully combined with NOMAC in a monophasic oral contraceptive. Two recently published randomized controlled trials demonstrate that NOMAC-E2 is an effective contraceptive, with a Pearl Index less than one pregnancy per 100 woman-years. The bleeding pattern on NOMAC-E2 is characterized by fewer bleeding/spotting days, shorter withdrawal bleeds, and a higher incidence of amenorrhea than the comparator oral contraceptive containing drospirenone and ethinyl estradiol. The adverse event profile appears to be acceptable. Few severe adverse events were reported in the randomized controlled trials. The most common adverse events were irregular bleeding, acne, and weight gain. Preliminary studies suggest that NOMAC-E2 does not seem to have negative effects on hemostatic and metabolic parameters. While no one oral contraceptive formulation is likely to be the optimum choice for all women, NOMAC-E2 is a formulation with effectiveness comparable with that of other oral contraceptives, and a reassuring safety profile.

Characteristics and metabolic effects of estrogen and progestins contained in oral contraceptive pills

Estrogen and progestins have been used by millions of women as effective combined oral contraceptives. Oral contraceptives (OCs) modify surrogate markers such as lipoproteins, insulin response to glucose, and coagulation factors, that have been associated with cardiovascular and venous risk. Ethinyl-Estradiol (EE) exerts a stronger effect that natural estradiol (E2) on hepatic metabolism. New progestins with high specificity have been designed to avoid interaction with other receptors and prevent androgenic, estrogenic or glucocorticoid related side-effects. The risks and benefits of new progestins used in contraception depend upon their molecular structure, the type and dose of associated estrogen, and the delivery route. The lower impact of E2-based combinations on metabolic surrogate markers may result in an improved safety profile, but only clinical outcomes are relevant to assess the risk. Large surveillance studies are warranted to confirm this hypothesis.

The use of an oral contraceptive containing estradiol valerate and dienogest before office operative hysteroscopy: a feasibility study

To investigate the impact of a 3 months preoperative administration of an oral contraceptive, containing dienogest (DNG) and estradiol valerate (E₂V) on the outcome of office operative hysteroscopy (OOH). One-hundred and forty-two patients diagnosed at office hysteroscopy as having an asynchronous endometrium associated with either a broad-base sessile endometrial polyp (>1.5, <2.5 cm) or a uterine septum (>1/3 uterine cavity) or scheduled for tubal sterilization were enrolled into a prospective case-control study at University "Federico II" of Naples. 86/142 patients accepted the preoperative hormonal treatment (Group A), while 56/142 refused, thus becoming controls (Group B). Group A underwent OOH during the 10th-20th days of the third cycle of treatment. In Group B OOH was performed at enrolment, together with the diagnostic procedure. The study outcomes were: endometrial pattern, success rate, operating time, degree of surgical difficulty and pain score. An overall improvement of the endometrium was reported in 100% of cases in Group A. A statistically significant difference in success rate could not be demonstrated between two groups. Operative procedures were performed significantly quicker and easier in Group A than Group B (p < 0.001 and p < 0.05, respectively). The mean Visual Analog Scale (VAS) score was significantly lower in Group A (p < 0.001). A short pretreatment with combined oral contraceptive (COC) containing E₂V/DNG seems to have a favorable impact on endometrium which in turn may result in an improvement of the overall outcomes of OOH.

Medical treatment of idiopathic heavy menstrual bleeding. What is new? An evidence based approach

BACKGROUND

Heavy menstrual bleeding (HMB) is an important health problem affecting up to 30 % of reproductive age women, interfering with their quality of life. Medical therapy, with the avoidance of unnecessary surgery, is an attractive option.

PURPOSE

To provide a comprehensive review of the current medical treatments available for idiopathic HMB and to focus on the newly introduced modalities. Furthermore, to provide a practical algorithm based on the best available evidence.

METHODS

A PubMed search was conducted looking for the different trials, reviews and various guidelines relating to medical treatment of idiopathic HMB.

RESULTS

The most effective medical treatment for idiopathic HMB is the levonorgestrel-releasing intrauterine system. It provides a reliable long-term effect. Importantly, there is a growing scientific evidence for new modalities entailing; modified-release formulation of tranexamic acid, the new four-phasic estradiol valerate/dienogest contraceptive pills and combined contraceptive vaginal ring. Also, vaginal danazol has been tried.

CONCLUSION

Maintenance of status quo, i.e., keeping first-line treatment of idiopathic HMB as medical treatment is an essential issue. Modified-release formulation of tranexamic acid, the new four-phasic contraceptive pills and contraceptive vaginal ring are recently added to the medical armamentarium for treatment of idiopathic HMB increasing its efficacy.

Estradiol valerate/dienogest: a novel combined oral contraceptive

BACKGROUND

Estradiol valerate/dienogest (E2V/DNG) is a combined oral contraceptive (COC) with 2 new hormonal entities and a unique 4-phasic dosing regimen indicated for women to prevent pregnancy.

OBJECTIVE

The purpose of this article is to review the pharmacology, pharmacokinetics, clinical efficacy, tolerability, and cost of E2V/DNG.

METHODS

MEDLINE (1966-June 2011) and EMBASE (1966-June 2011) were searched for original research and review articles published in the English language using the terms Natazia or Qlaira or estradiol valerate and dienogest. The reference lists of identified articles were reviewed for additional pertinent publications. Abstracts from the 2005 to 2011 American Society of Reproductive Medicine and American College of Obstetricians and Gynecologists meetings were searched using the same terms.

RESULTS

The search provided 56 articles that addressed the pharmacology, pharmacokinetics, pharmacodynamics, clinical efficacy, and tolerability of E2V/DNG in women of reproductive age. Articles reporting efficacy or tolerability in the setting of menopause were excluded. The initial efficacy of E2V/DNG on ovulation inhibition was investigated in 2 prospective, randomized, open-label, Phase II dose-finding studies. The dose that was approved by the Food and Drug Administration resulted in 3.13% of women ovulating in the second cycle of treatment (90% CI, 0.2%-6.05%). Rate of pregnancy prevention with this agent was reported with a Pearl Index ranging from 0.73 to 1.27 (unadjusted) to 0.34 to 0.72 (adjusted for method failure only). The mean duration of withdrawal bleeding was 4.3 days (range, 4.0-4.6 days) among 2266 women receiving 13 treatment cycles. Adverse events reported in >1% of patients included abdominal pain, acne, breast pain, dysmenorrhea, emotional lability, headache, nausea, and weight increase.

CONCLUSIONS

Estradiol valerate/dienogest is a new contraceptive formulation. It offers efficacy, tolerability, and an acceptable safety profile with a potentially better bleeding pattern than levonorgestrel-containing COCs. This COC may be especially useful for older women of reproductive age who are adherent to therapy and looking for shorter and/or lighter menstrual cycles. Studies will need to be performed to determine whether clinically significant differences in outcomes exist among E2V/DNG and other available COCs.

Quadriphasic versus monophasic oral contraceptives for contraception

BACKGROUND

Quadriphasic oral contraceptives have been developed to reduce the adverse effects of oral contraceptives and are presented as more physiological since they mimic the natural cycle. However, suggested disadvantages of quadriphasic oral contraceptives include a possible increased risk of pill-taking errors caused by the array of different color pills, complicated directions for catching up when a pill is missed, the higher price and potential inferiority in terms of side effects.

OBJECTIVES

To compare the contraceptive effectiveness, bleeding pattern, minor side effects and acceptability of quadriphasic contraceptive pills versus monophasic contraceptive pills.

SEARCH METHODS

We searched CENTRAL, MEDLINE, EMBASE, POPLINE, ClinicalTrials.gov and ICTRP for trials comparing quadriphasic pills with monophasic pills. We contacted researchers and manufacturers of quadriphasic oral contraceptives to identify additional studies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing quadriphasic with monophasic oral contraceptives . Trials had to report on contraceptive effectiveness, bleeding patterns, minor side effects, ease of use or trial discontinuation. We excluded studies where the intervention was primarily used as a treatment for disorders or was administered for fewer than three consecutive cycles.

DATA COLLECTION AND ANALYSIS

T wo authors abstracted and entered data into RevMan. We critically appraised the methodological quality of the included trials. For continuous variables, we computed the mean difference with 95% confidence interval (CI) using the random-effects model. For dichotomous variables, we calculated the risk ratio with 95% CI using the random-effects model.

MAIN RESULTS

We included one double-blind, double-dummy RCT comparing a quadriphasic oral contraceptive composed of dienogest and estradiol valerate with a monophasic oral contraceptive composed of levonorgestrel and ethinylestradiol. Contraceptive effectiveness, intracyclic bleeding and discontinuation due to side effects were similar for quadriphasic and monophasic pills. The number of women experiencing withdrawal bleeding was higher in the monophasic group compared to the quadriphasic group. Users of quadriphasic pills reported fewer bleeding/spotting days and fewer bleeding/spotting episodes than users of monophasic pills but the report did not specify whether the bleeding/spotting was scheduled or unscheduled. More women using quadriphasic oral contraceptives reported breast pain compared to women using monophasic oral contraceptives.

AUTHORS' CONCLUSIONS

The available evidence is insufficient to determine whether quadriphasic differ from monophasic oral contraceptives in contraceptive effectiveness, bleeding pattern, minor side effects and acceptability. Studies that compare quadriphasic and monophasic oral contraceptives with an identical progestogen and estrogen type are needed to determine whether the quadriphasic approach differs from the monophasic approach. Studies that compare quadriphasic pills with monophasic pills containing 30 μg ethinylestradiol are indicated to determine whether quadriphasic oral contraceptives have an advantage over the current, first choice oral contraceptive . Until then, we recommend monophasic pills containing 30 μg estrogen as the first choice for women starting oral contraceptive use.

The state of hormonal contraception today: benefits and risks of hormonal contraceptives: combined estrogen and progestin contraceptives

Discussion of effective birth control methods can be a challenging process for clinicians because the adoption and consistent use of contraception may be influenced by patients' fears, myths, and misperceptions. Over the years, new progestins have been included in combination contraceptives or are used alone to provide effective contraception as well as to decrease androgenic side effects and ameliorate the symptoms of premenstrual dysphoric disorder. Alternative delivery systems and regimens have also been introduced to improve tolerability and continuance and convenience of use. This is a review of estrogen and progestin combinations and their effects.

Estradiol valerate and dienogest: a new approach to oral contraception

Most combination oral contraceptives contain ethinyl estradiol and a progestin. A new and novel oral contraceptive formulation combines estradiol valerate (E2V) with dienogest (DNG) in a four-phase dosing regimen. 17β-estradiol is a naturally-occurring estrogen, and a contraceptive pill containing such an estrogen offers potential benefits with regard to metabolic side effects and adverse events. Dienogest is derived from 19-nortestosterone and exerts profound progestational effects on the endometrium, but it differs from other progestins in its class by its antiandrogenic activity. Estradiol valerate plus dienogest (E2V/DNG) is now available in a four-phasic regimen that integrates an estrogen stepdown and progestin stepup dosing approach along with a short two-day hormone-free interval. This regimen offers safe, reliable contraception and has been shown to be an effective treatment for heavy menstrual bleeding. Metabolic effects and adverse events appear similar to those reported with oral contraceptives containing ethinyl estradiol.

Preliminary study on the effect of four-phasic estradiol valerate and dienogest (E2V/DNG) oral contraceptive on the quality of sexual life

INTRODUCTION

A new oral contraceptive containing the natural estrogen estradiol and a 19-nortestosterone derivate dienogest (DNG) in a four-phasic 28-day regimen may be used by women.

AIM

To investigate the quality of sexual life of healthy women on estradiol valerate and DNG (E2V/DNG) oral contraceptive.

METHODS

Fifty-seven women (age range 18-48 years) were enrolled. The Short Form-36 (SF-36) questionnaire to assess quality of life (QoL) was administered at baseline and at the 26th day of both the 3rd and 6th cycles of oral contraceptive (OC) intake. The Short Personal Experience Questionnaire (SPEQ) to measure the change of sexual behavior was used at the 2nd, 7th, 14th, 21st, 26th, and 28th days of the baseline cycle, as well as at the same days of both the 3rd and 6th cycle of contraceptive intake.

MAIN OUTCOME MEASURE

The SF-36 and the SPEQ questionnaires.

RESULTS

Women reported QoL improvement at the 3rd (P < 0.05) and at the 6th cycles (P < 0.01). By SPEQ, improvement of sexuality during the 3rd and the 6th cycle with respect to baseline experience was observed (P < 0.05). The frequency of sexual activity remained basically unchanged (P = NS). Enjoyment and desire improved at the 6th cycle with respect to the 3rd cycle (P < 0.05). All women reported decreased dyspareunia at the 3rd and 6th cycles (P < 0.05). Interestingly, desire, arousal, orgasm, enjoyment, and sexual activity improved, reaching a peak around the 14th day of the menstrual cycle (P < 0.05). At the 3rd and 6th cycle, women on OCs were sexually cyclic, but the peak improvement of desire, arousal, orgasm, enjoyment, and sexual activity appeared around the 7th day of OC intake (P < 0.05).

CONCLUSION

Reduced hormone-free interval is a new concept in low-dose OC regimens. Moreover, the E2V/DNG multiphasic extended regimen has been found to positively modify the sexuality of users.

Metabolic effects of contraceptive steroids

Estrogen and progestins have been used by millions of women as effective combined contraceptives. The safety of hormonal contraceptives has been documented by years of follow-up and serious adverse events that may be related to their use are rare in the young population exposed to these agents. The balance between the benefits and the risks of contraceptive steroids is generally positive in particular when comparing to the risks of pregnancy and especially in women with risk factors. The metabolic changes induced by the synthetic steroids used in contraception, such as lipoprotein changes, insulin response to glucose, and coagulation factors have been considered as potential markers of cardiovascular and venous risk. Observations of these effects have led to modifications of the composition of hormonal contraceptive in order to minimize these changes and hence potentially decrease the risks. The synthetic estrogen Ethinyl-Estradiol (EE) exerts a stronger effect that natural estradiol (E2) on hepatic metabolism including estrogen-dependent markers such as liver proteins. This stronger hepatic impact of EE has been related to its 17α-ethinyl group which prevents the inactivation of the molecule and results in a more pronounced hepatic effect of EE as compared to estradiol. Due to its strong activity, administering EE via a non-oral route does not prevent its impact on liver proteins. In order to circumvent the metabolic changes induced by EE, newer products using more natural compounds such as estradiol (E2) and estradiol valerate (E2V) have been introduced. The synthetic progestins used for contraception are structurally related either to testosterone (T) (estranes and gonanes) or to progesterone (pregnanes and 19-norpregnanes). Several new progestins have been designed to bind more specifically to the progesterone receptor and to minimize side-effects related to androgenic, estrogenic or glucocorticoid receptor interactions. Dienogest (DNG), and drospirenone (DRSP) and the 19-norpregnanes including Nestorone® (NES), nomegestrol acetate (NOMAc) and trimegestone (TMG) have been combined with estrogen either EE or E2 or estradiol valerate (E2V). Risks and benefits of the newer progestins used in contraception depend upon the type of molecular structure, the type and dose of estrogen associated in a combination and the route of administration. The lower metabolic impact of estradiol-based combinations may result in an improved safety profile, but large surveillance studies are warranted to confirm this plausible hypothesis. So far, the contraindications and warnings for use of current COCs also apply to the estradiol-based COCs.

Estrogen and thrombosis: controversies and common sense

Soon after the introduction of hormonal oral contraceptive agents reports of thrombotic complications appeared. In the past several decades, large epidemiological studies helped defined these risks for both arterial and venous complications. Clinicians can assess a patient's risk of thrombosis by both composition of the agent and patients' personal risk factors. For women with bleeding disorders these prothrombotic changes can help decrease bleeding complications. There is now also abundant data on future management of patients with estrogen related thrombosis.