Differential effects of progestins on hemostasis

The drospirenone (DRSP)-only pill: clinical implications in the daily use

OBJECTIVES

Progestins used in contraception are either components of combined hormonal contraceptives or are used as a single active ingredient. Progestins are highly effective in long-term contraception and have a very good safety profile with very few contraindications.

METHODS

An oestrogen-free ovulation inhibitor POP has been authorised in the USA and the EU. It contains 4 mg of drospirenone (DRSP). The hormone administration regimen of 24 days followed by a 4-day hormone-free period was chosen to improve bleeding control and to maintain oestradiol concentrations at early follicular- phase levels, preventing oestrogen deficiency.

RESULTS

Clinical trials have demonstrated high contraceptive effectiveness, a very low risk of cardiovascular risk events and a favourable bleeding pattern. Due to the long half-life of DRSP (30-34 h), the effectiveness is maintained even in case of a forgotten pill on a single occasion. Studies involving deliberate 4 days in one cycle 24-hour delays in taking a pill have demonstrated that ovulation inhibition is maintained if a single pill is missed.

CONCLUSIONS

This review article will describe the clinical impact in the daily use of the 4 mg DRSP only pill and the resulting data on the effectiveness and safety of this hormonal contraceptive.

Association of Progestogens and Venous Thromboembolism Among Women of Reproductive Age

OBJECTIVE

To evaluate associations between use of seven progestogens and incident acute venous thromboembolism (VTE) among women of reproductive age.

METHODS

This nested matched case-control study identified women aged 15-49 years from January 1, 2010, through October 8, 2018, in the IBM MarketScan databases, a nationwide sample of private insurance claims in the United States. After exclusions, 21,405 women with incident acute VTE (case group), identified by diagnosis codes, were matched 1:5 by year of birth and index date through risk set sampling to 107,025 women without prior VTE (control group). From lowest to highest systemic dose based on a modified hierarchy, progestogens studied were levonorgestrel-releasing intrauterine device (LNG-IUD), oral norethindrone, etonogestrel implant, oral progesterone, oral medroxyprogesterone acetate, oral norethindrone acetate, and depot medroxyprogesterone acetate (DMPA). Conditional logistic regression models adjusted for 16 VTE risk factors were used to estimate odds ratios and 99% CIs for incident acute VTE associated with current progestogen use compared with nonuse. The primary analysis treated each progestogen as a binary exposure. Dose, which varied for oral formulations, and chronicity were explored separately. Significance was set at P <.01 to allow for multiple comparisons.

RESULTS

Current use of higher-dose progestogens was significantly associated with increased odds of VTE compared with nonuse (oral norethindrone acetate: adjusted odds ratio [aOR] 3.00, 99% CI 1.96-4.59; DMPA: aOR 2.37, 99% CI 1.95-2.88; and oral medroxyprogesterone acetate: aOR 1.98, 99% CI 1.41-2.80). Current use of other progestogens was not significantly different from nonuse (LNG-IUD, etonogestrel implant, and oral progesterone) or had reduced odds of VTE (oral norethindrone). Sensitivity analyses that assessed misclassification bias supported the primary findings.

CONCLUSION

Among reproductive-aged women using one of seven progestogens, only use of norethindrone acetate and medroxyprogesterone acetate-considered higher-dose progestogens-was significantly associated with increased odds of incident acute VTE. The roles of progestogen type, dose, and indication for use warrant further study.

Bleeding profile of women with cardiovascular risk factors using a drospirenone only pill with 4 mg over nine cycles compared to desogestrel 0.075 mg

OBJECTIVE

Progestin-only pills are associated with irregular bleeding patterns, including amenorrhea. Desogestrel (DSG) 75 mcg, a pill that inhibits ovulation, shows poor cycle control that may harm acceptability and compliance. A Drospirenone (DRSP)-only pill was developed with 24 & 4 days of active & placebo days every 28-day cycle to improve cycle control.

STUDY DESIGN

A phase III study in healthy women aged 18 to 45 years was performed to compare the bleeding profile of women taking a DRSP versus DSG over nine cycles. 249 women were older > 35 years: 173 using DRSP and 73 DSG. 259 women had a BMI > 25 kg/m²: 189 using DRSP and 70 DSG and 340 women were smokers: 237 using DRSP and 103 DSG. The amount of unscheduled bleeding/spotting days was analyzed in each of these sub-groups and compared statistically.

RESULTS

Age: During cycles 2-4, the mean number of unscheduled bleeding days and spotting was 8.1 (SD10.53) for DRSP and 20.1 (19.41) for DSG; p = .0089. BMI > 25 kg/m²: During cycles 2-4 the mean number of unscheduled bleeding days and spotting was 7.8 (SD 12.18) for DRSP and 17.7 for DSG (SD 19.39); p = .0001. Smokers: During cycles 2-4, the mean number of unscheduled bleeding days and spotting was 9.6 (SD 11.69) for DRSP and 17.4 for DSG (SD 17.47); p = .0016.

CONCLUSIONS

These analyses show the improvement in the bleeding profile of women with specific cardiovascular risk factors using the DRSP only oral contraceptive product compared to DSG.ImplicationsAn improvement in the bleeding profile of women with specific cardiovascular risk factors like age > 35 years, BMI > 25kg/m², and smokers using the DRSP only oral contraceptive product is described.Herby a higher contraceptive efficacy in these patients that additionally benefit from estrogen-free contraceptive methods is expected.

Norethisterone and its acetate - what's so special about them?

INTRODUCTION

Progestogens (progestins) are widely used for contraception, in postmenopausal hormone therapy, and in treatment of abnormal uterine bleeding and endometriosis. Norethisterone (NET) and its acetate (NETA) differ from other progestogens by their partial conversion to ethinylestradiol (EE). We review their special characteristics and focus on the clinically relevant risk factors associated with estrogen action, such as migraine with aura and risk of thrombosis.

METHODS

Narrative review based on a medical literature (OvidMedline and PubMed) search.

RESULTS

NET converts to significant amounts of EE; 10-20 mg NET corresponds to 20-30 µg EE. The effects of NET on the endometrium are pronounced, making it a good choice for treating abnormal uterine bleeding, endometriosis, and endometrial hyperplasia. NET also has beneficial effects on bone mineral density and positive or neutral effects on cardiovascular health. Conversely, long-term use of NET is associated with a slightly increased breast cancer risk, and the risk of venous thromboembolism is moderately increased. This risk seems to be dose-dependent; contraceptive use carries no risk, but therapeutic doses might be associated with an increased risk. Studies suggest an association between combinations of EE and progestogens and ischaemic stroke, which in particular concerns women with migraine. No studies have, however, assessed this risk related to the therapeutic use of NET.

CONCLUSIONS

NET is a potent progestogen, especially when considering the endometrium. Its partial conversion to EE, however, is important to remember. Clinical consideration is required with women at high risk for either breast cancer or thromboembolism, or experiencing migraine with aura.

Hormonal Contraceptives and the Risk of Venous Thrombosis

The risk of venous thrombosis (VT) varies according to the type of progestogen that is found in combined oral contraceptives (COCs). When combined with the estrogen component ethinylestradiol (EE), the androgenic progestogens are better able to counteract the EE-induced stimulation of liver proteins and hence are associated with a twofold decreased risk of VT compared with non- or antiandrogenic progestogens, which exert limited counteraction of EE. Because EE is responsible for the increased risk, novel estrogens such as estradiol were developed and seem to have a lower risk of VT than EE. Besides COCs, there are other methods of hormonal contraceptives, such as progestogen-only contraceptives, which do not increase VT risk, except for injectables. Other nonoral contraceptives are combined vaginal rings and patches. There is insufficient evidence regarding the risk of VT associated with these two methods compared with COCs. The increased risk associated with COCs is more pronounced in women with inherited thrombophilia. In these women, the progestogen levonorgestrel seems to be associated with the lowest risk of VT. Currently, there are no studies that have investigated the risk of VT in women who switch COCs. We hypothesize that switching COCs, even when switching from a high- to a low-risk COC, increases the risk of VT. Finally, risk prediction models in women who use COCs are lacking. Since there is a large number of VT cases associated with COC use, it is important to identify women at risk of VT and advise them on alternative contraception methods.

Efficacy and cardiovascular safety of the new estrogen-free contraceptive pill containing 4 mg drospirenone alone in a 24/4 regime

Background

A new estrogen-free contraceptive has been approved by both the FDA and more than 15 European authorities. It is composed of drospirenone (DRSP) at a dosage of 4 mg in a regimen 24/4. The molecule is known to have anti-gonadotropic, anti-mineralocorticoid, anti-estrogenic, and antiandrogenic properties. The purpose of these clinical trials with a new estrogen-free contraceptive was to introduce a contraceptive method with high efficacy and showing a profile with low cardiovascular risks.

Methods

Three European and American multicenter clinical trials have been conducted in more than 2500 patients and more than 25,000 cycles, not only demonstrating an excellent efficacy (Pearl Index of 0.73) but also investigating possible cardiovascular risks. In the USA study, 422 participants (41.9%) had a risk factor for VTE, while in the European studies, 261 patients (16.6%) had at least one VTE risk factor. Amount of arterial and venous thromboembolic events, hemostasiological data, blood pressure development, and ECG data were evaluated.

Results

No single case of VTE was documented, no changes in hemastosiological parameters were observed, a small decrease in RR in patients with pretreatment values between 130 and 140 and/or 85 to 90 mm HG and no influence on ECG parameters were observed.

Conclusions

The introduction of a new estrogen-free contraceptive with 4 mg of non-micronized drospirenone in a 24/4-day regimen expands contraception options for women as not only a high efficacy could be demonstrated during clinical trials but also a very high cardiovascular safety profile was observed even in women with cardiovascular risk factors.

Trial registration

EudraCT registration numbers: 2010–021787-15 & 2011–002396-42. Clincaltrials.gov: NCT02269241.

Safety, influence on the endometrium, sonographic changes and bleeding profile after 13 cycles with the new drospirenone only pill (DOP) for contraception

Background

The primary objective of the present trial was to assess the endometrial safety of a new oral contraceptive containing 4 mg drospirenone for a total duration of 13 cycles of 28 days each: 24 days of active treatment followed by 4 days placebo treatment per treatment cycle.

Materials and methods

This was a single-center, open-label, multiple-dose study on healthy female subjects at risk of pregnancy. Twenty one (= safety population set) pre-menopausal female Caucasian subjects started treatment with the study medication. The mean age was 29.0 years (range 19.0–36.0 years). Four subjects terminated the trial prematurely for the following reasons: on the subject’s request (n=2), due to an adverse event (n=1) and due to loss of contact (n=1). Seventeen subjects completed the planned duration of 13 cycles of open treatment with the test product (each cycle of 28 days).

Results

At visit 1 (pre-treatment), the biopsy result in the safety population set was proliferative in 14 cases and secretory in seven cases. At visit 7, four cases showed an inadequate result (insufficient tissue for diagnosis), 12 as proliferative and three as secretory. The number of biopsies with proliferative and secretory results reduced under treatment (safety population). The pre-post treatment changes in the endometrial biopsy results in the treatment completers set (n=17) showed almost no differences. At visit 1 (pre-treatment), the biopsy result was proliferative in 12 cases and secretory in five cases. At visit 7 (after 13 cycles of 28 days), four cases showed an inadequate result (insufficient tissue for diagnosis), 11 as proliferative, and two as secretory. The mean endometrial thickness in the safety population was reduced from 8.3 mm at visit 1 to 6.0 mm at visit 7. When comparing the endometrial thickness in the 21 subjects (safety population), the endometrial thickness showed a pre-post difference of 2.1 mm, whereas the endometrial thickness in the 17 study completers showed a pre-post difference of 2.5 mm (8.2 mm at visit 1–5.6 mm at visit 7).

Conclusions

Drospirenone 4 mg film-coated tablet in a dosage regime of 24/4 days is, regarding endometrial histology, a safe drug. Trial registration: EudraCT Register number: 2013-002300-13.

Multicenter, phase III trials on the contraceptive efficacy, tolerability and safety of a new drospirenone-only pill

INTRODUCTION

Approximately 100 million women currently use combined oral contraceptives. Combined oral contraceptives use is associated with increased risk of venous thromboembolic events and cardiovascular disease. Progestin-only pills do not increase the risk of venous thromboembolic events, stroke and myocardial infarction but are associated with a poor cycle control. A novel estrogen-free pill containing only drospirenone (DRSP) was developed to improve bleeding pattern, tolerability and acceptance without increasing venous thromboembolic events risks in contraception.

MATERIAL AND METHODS

Two prospective, multicenter Phase III studies in healthy women aged 18-45 years were performed to demonstrate the efficacy and safety of a drospirenone-only pill in a regimen of 24 days of 4 mg of drospirenone tablets followed by 4 days of placebo. A total of 1571 women (14 329 exposure cycles) were analyzed: 713 patients in the 13-cycle study 1 with 7638 exposure cycles and 858 patients in the 9-cycle study 2 with 6691 exposure cycles. The primary endpoint was the overall Pearl index, calculated for each study separately, and for both pooled. As main secondary efficacy endpoint, the "method failure Pearl index" including all pregnancies during "perfect medication cycles" was evaluated. EudraCT registration numbers: 2010-021787-15 & 2011-002396-42.

RESULTS

Calculations on pooled studies 1 and 2 with 1571 patients gave an overall Pearl index (based on 14 329 cycles) of 0.7258 (95% CI 0.3133 to 1.4301). No single case of deep vein thrombosis or pulmonary embolism and only one case of hyperkalemia were reported. Additional information such as laboratory parameters, body mass index, bodyweight, heart rate and blood pressure showed no statistically significant changes due to the treatment.

CONCLUSIONS

This is the first report of a new drospirenone-only oral contraceptive providing clinical efficacy similar to combined oral contraceptives, with a good safety profile, and favorable cycle control.

Impact of progestogens on hemostasis

Combined hormonal contraception containing estrogen and progestogen and postmenopausal hormone therapy with estrogen ± progestogen are reported risk factors for venous thrombosis. The thrombotic risk varies by estrogen dose and type of progestogen. Estrogen combined with "newer generation" progestogens in combined oral contraceptives may have higher thrombotic risk than estrogen combined with older generation progestogens. Among postmenopausal women thrombotic risk also varies by type of hormone and mode of delivery. Although the risk of thrombosis with the different hormonal compounds is uncertain, it has definitely been attributed to the pharmacological effect of the hormones on hemostasis. Animal and cell culture studies have demonstrated the pharmacodynamics of progestogens with respect to hemostasis. Extrapolation from these studies to clinical conditions and further to clinical end points such as cardiovascular disease is, however, controversial. Few clinical studies have focused on the effect of progestogen only therapy on the hemostatic system in vivo. Most of the current knowledge regarding the in vivo effect of progestogens on hemostasis is obtained from studies with combined contraceptives. These results obviously reflect the combined influence of both estrogen and progestogen on hemostasis, and extrapolation to progestogen-only conditions is challenging. This paper discusses the pharmacodynamics of progestogens in relation to the hemostatic system, addressing results obtained in animal and cell culture studies and in clinical studies employing progestogen-only and combined oral contraceptives. The compiled results suggest that the major effect of progestogens on hemostasis is related to alterations in platelet function and the tissue factor pathway of coagulation. More studies focusing on these topics are warranted.

Drospirenone as estrogen-free pill and hemostasis: coagulatory study results comparing a novel 4 mg formulation in a 24 + 4 cycle with desogestrel 75 μg per day

INTRODUCTION

A novel estrogen free contraceptive pill, with drospirenone 4 mg in a dosing regimen of 24 + 4, has been developed with a pearl-index of 0.51 (95% CI 0.1054; 1.4922). The aim of the following study was to determine if 4 mg DRSP has an impact on coagulation factors and thrombotic risks in comparison with desogestrel 75 μg.

PATIENTS AND METHODS

Thirty-nine patients received 4 mg DRSP 24 + 4 d and 29 desogestrel 75 μg per day continuously during nine complete cycles. Following hemostatic parameters were evaluated: Apc resistance, Antithrombin III, Protein C reactivity, Factor VII, Factor VIII, and d-Dimer.

RESULTS

Factor VII decreased from 1.123 to 1.066 in the DRSP group and from 1.241 to 1.034 in the desogestrel group (p = 0.0088). The difference in change of mean Protein C activity from baseline to endpoint was -0.0332 in the DRSP versus -0.157 in the desogestrel group (p = 0.0249). d-Dimer values dropped in the DRSP group from baseline values of 264.9-215.0 ng/mL, whereas in the desogestrel group there was a rise from 201.4 ng/mL to 281.5 ng/mL.

DISCUSSION

DRSP 4 mg was not associated with any meaningful changes on hemostatic parameters, indicating a lack of effect on hemostasis.

Natural Micronized Progesterone Sustained Release (SR) and Luteal Phase: Role Redefined!!

Role of progesterone in reproductive medicine is evolving with its suggested clinical role for the hormonal and nonhormonal actions in reproductive medicine. The main function of progesterone is to induce 'secretory' changes in endometrium that is further complimented by its immunomodulatory and anti-inflammatory actions. It positively modulates PIBF, NK cells and HOXA 10 genes for better implantation. MHRA recommends Serum Progesterone levels ≥14ng/ml in the mid-luteal phase for supporting pregnancy adequately. Oral Natural Micronized Progesterone SR formulation represents a therapeutic advance in this direction offering 'therapeutic compliance' with oral formulation while avoiding the local side effects related to long-term patient compliance in reproductive disorders. The formulation offers round the clock efficiency and efficacy with single dose administration thereby improving patient convenience and compliance. This formulation has been marketed globally since 1986 utilizing the well validated drug delivery system involving Methylcellulose base. The clinical utility of this formulation is further suggested especially in various conditions related with luteal phase insufficiency and Bad obstetric history (BOH) or luteal phase support in ART. The level of evidence has been quite robust with several clinical studies including Prescription Event Monitoring and Investigator initiated studies supporting the clinical role of oral NMP SR formulation especially in 'Real world' clinic settings for Luteal phase insufficiency that may be physiological or iatrogenic.

Comparison of the impact of four generations of progestins on hemostatic variables

This study was undertaken to evaluate the impact of progestins as part of low-estrogen (ethinyl estradiol [EE2] ≤35 μg) combined oral contraceptives (COCs) on hemostatic variables. One hundred ninety-five healthy women took oral contraceptives with following formulations: 35 EE2/norgestimate (NGM), 35 EE2/cyproterone acetate, 35 EE2/norethisterone, 30 EE2/levonorgestrel, 30 EE2/drospirenone (DRSP), 20 EE2/gestodene, and 20 EE2/DRSP, for 6 months. Hemostatic assays (prothrombin time, activated partial thromboplastin time, fibrinogen, resistance to activated protein C ratio, protein C, protein S, factor VIII [FVIII], antithrombin, plasminogen, α2-antiplasmin, inhibitor of plasminogen activator type 1 [PAI-1] and d-dimers) were performed in 3 time points: at baseline, after 3, and 6 cycles. For each formulation, results were compared according to baseline values, intergroup analysis, and the amount of estrogen or progestin component. Most of the variables were changed except FVIII. Significant difference between oral contraceptives was found in antithrombin, protein C, protein S activities, and PAI-1 values, but changes were mostly within reference range.

Contraceptives with novel benefits

INTRODUCTION

Progesterone receptor (PR) agonists (progestins) and antagonists are developed for female contraceptives. However, non-contraceptive applications of newer progestins and PR modulators are being given more attention.

AREAS COVERED

The newer PR agonists including drospirenone, nomegestrol, trimegestone, dienogest and nestorone are being evaluated as contraceptives with health benefits because of their unique pharmacological properties. The selective PR modulators (SPRM; PR antagonists with PR agonistic properties) are under development not only for emergency contraception but also for other health benefits such as the treatment of endometritis and leiomyoma. After searching the literature from PubMed, clinicaltrials.gov and patent database, this review focuses on the effects and mechanisms of these progestins, and SPRMs as contraceptives with other health benefits.

EXPERT OPINION

PR agonists and antagonists that have novel properties may generate better contraceptive effects with other health benefits.

State of the Art Review: Emerging Therapies: The Use of Insulin Sensitizers in the Treatment of Adolescents with Polycystic Ovary Syndrome (PCOS)

PCOS, a heterogeneous disorder characterized by cystic ovarian morphology, androgen excess, and/or irregular periods, emerges during or shortly after puberty. Peri- and post-pubertal obesity, insulin resistance and consequent hyperinsulinemia are highly prevalent co-morbidities of PCOS and promote an ongoing state of excess androgen. Given the relationship of insulin to androgen excess, reduction of insulin secretion and/or improvement of its action at target tissues offer the possibility of improving the physical stigmata of androgen excess by correction of the reproductive dysfunction and preventing metabolic derangements from becoming entrenched. While lifestyle changes that concentrate on behavioral, dietary and exercise regimens should be considered as first line therapy for weight reduction and normalization of insulin levels in adolescents with PCOS, several therapeutic options are available and in wide use, including oral contraceptives, metformin, thiazolidenediones and spironolactone. Overwhelmingly, the data on the safety and efficacy of these medications derive from the adult PCOS literature. Despite the paucity of randomized control trials to adequately evaluate these modalities in adolescents, their use, particularly that of metformin, has gained popularity in the pediatric endocrine community. In this article, we present an overview of the use of insulin sensitizing medications in PCOS and review both the adult and (where available) adolescent literature, focusing specifically on the use of metformin in both mono- and combination therapy.

Tailoring combination oral contraceptives to the individual woman

BACKGROUND

Over the last 50 years, there has been intense interest in the type of progestin used in combined oral contraceptives (COC) in an attempt to exploit novel properties and minimize adverse events. At the same time, the dose of synthetic estrogen, ethinylestradiol, in COC pills has been reduced to minimize risks for ischemic stroke, myocardial infarction, and venous thromboembolism. New formulations, including extended-cycle or continuous-use COCs or those that use a natural estrogen, estradiol, may offer improvements over their predecessors.

METHODS

A Medline search was performed to encompass studies published since 1990 that pertain to the pharmacology of estrogens and progestins used in COCs, risks and adverse events associated with COCs, and extended or continuous-use COCs.

RESULTS

New progestins structurally related to progesterone and spironolactone may exhibit more selective binding to the progesterone receptor and lack androgenic adverse effects associated with progestins structurally related to testosterone. Recently, COCs containing natural (17β-estradiol) or conjugated estrogen (estradiol valerate) rather than ethinylestradiol have been developed in order to move to a more natural estrogen. Although many of the new progestins incorporated into COCs have not demonstrated the negative effects on lipid metabolism and other adverse events associated with the traditional progestins, the goal of attaining good cycle control has yet to be achieved. Extended-cycle and continuous-use regimens are now available that reduce the frequency of menses, but breakthrough bleeding remains a problem.

CONCLUSIONS

Appropriate counseling to raise awareness of the specific characteristics of the different COC options available may optimize adherence and patient acceptability.

Synthetic progestins induce growth and metastasis of BT-474 human breast cancer xenografts in nude mice

OBJECTIVE

Previous studies have shown that sequential exposure to estrogen and progesterone or medroxyprogesterone acetate (MPA) stimulates vascularization and promotes the progression of BT-474 and T47-D human breast cancer cell xenografts in nude mice (Liang et al, Cancer Res 2007, 67:9929). In this follow-up study, the effects of progesterone, MPA, norgestrel (N-EL), and norethindrone (N-ONE) on BT-474 xenograft tumors were compared in the context of several different hormonal environments. N-EL and N-ONE were included in the study because synthetic progestins vary considerably in their biological effects and the effects of these two progestins on the growth of human tumor xenografts are not known.

METHODS

Estradiol-supplemented intact and ovariectomized immunodeficient mice were implanted with BT-474 cells. Progestin pellets were implanted simultaneously with estradiol pellets either 2 days before tumor cell injection (ie, combined) or 5 days after tumor cell injections (ie, sequentially).

RESULTS

Progestins stimulated the growth of BT-474 xenograft tumors independent of exposure timing and protocol, MPA stimulated the growth of BT-474 xenograft tumors in ovariectomized mice, and progestins stimulated vascular endothelial growth factor elaboration and increased tumor vascularity. Progestins also increased lymph node metastasis of BT-474 cells. Therefore, progestins, including N-EL and N-ONE, induce the progression of breast cancer xenografts in nude mice and promote tumor metastasis.

CONCLUSIONS

These observations suggest that women who ingest progestins for hormone therapy or oral contraception could be more at risk for developing breast cancer because of proliferation of existing latent tumor cells. Such risks should be considered in the clinical setting.

A review of the cardiovascular and breast actions of drospirenone in preclinical studies

OBJECTIVE

Hormone therapy is effective for the relief of menopausal symptoms. For women with a uterus, addition of a progestogen is required to protect the endometrium. However, synthetic progestins differ in certain pharmacological characteristics that may have implications for clinical practice. This literature-based review explores differences in the preclinical and clinical profiles of the progestins used in hormone therapy, focusing on their effects on the cardiovascular system and breast.

DESIGN

Studies included are selected based on criteria of relevance, topicality, and subjective assessment of quality, following comprehensive searches of online databases.

RESULTS

The biological actions of progestins depend on their receptor binding affinity profiles as well as their specific effects on progesterone receptor signaling, which often differ based on the ligand. Observational studies indicate that hormone therapies which include medroxyprogesterone acetate and certain other progestins may attenuate the cardiovascular benefits of estrogen and add to risk of breast cancer. Appraisal of the evidence suggests these clinical effects correlate with the progestin's pharmacological profile. Among the newer progestins, drospirenone has been investigated extensively in preclinical studies. With a pharmacological profile similar to progesterone, drospirenone is devoid of estrogenic, androgenic and glucocorticoid activity and possesses potent antialdosterone and antiandrogenic activity. This profile of drospirenone contrasts with that of older progestins, conferring specific effects on cardiovascular and breast cells.

CONCLUSIONS

The relative risks associated with hormone therapy vary with the combination of hormones included. Differences in pharmacological profile among progestins may translate to characteristic divergences in clinical profile, with potential implications for long-term health.

Advantages and challenges of oestrogen-free hormonal contraception

BACKGROUND

Not all women tolerate hormonal contraceptives containing oestrogens.

METHODS

The authors selected and evaluated relevant publications on the advantages and challenges of oestrogen-containing and oestrogen-free oral contraceptives obtained from the MEDLINE and Google databases from January 2000 to January 2010. In addition, the reference lists from the obtained publications as well as the authors' clinical experience served as additional sources of information. Emphasis was placed on the common adverse effects and risks associated with oestrogen replacement as well as on the noncontraceptive benefits of combined oral contraceptive pills and progestogen-only pills in the management of menstrual cycle-dependent problems.

FINDINGS

Progestogen-only pills have the potential to abolish many of the common adverse effects associated with oestrogen plus progestogen oral contraceptives and can be used to treat various menstrual cycle-dependent problems. However, only a limited number of clinical comparative studies are available. Progestogen-only pills are associated with a more irregular bleeding pattern than contraceptive pills containing oestrogens, especially during the first few months of therapy. As this is not permanent, adequate counselling is essential in order to prevent unnecessary discontinuation of treatment.

CONCLUSIONS

Progestogen-only pills offer an effective, convenient, and readily reversible method of contraception that is suitable for women with contraindications for oestrogens.

Pharmacology of different progestogens: the special case of drospirenone

The pharmacological properties of progestins used in contraception and hormone replacement therapy (HRT) vary, depending upon the molecules from which they are derived. Very small structural changes may induce considerable differences in effects. It is unclear if the currently available progestins are able to bind specifically to the progesterone receptors, PR-A or PR-B. The clinical relevance of more specific binding to one or the other isoforms of the progesterone receptor is still unknown. The development of new generations of progestins, with improved receptor-selectivity profiles, has been a great challenge. Steroidal and non-steroidal progesterone agonists have also been synthesized, although these molecules are at a very early stage of development. Several new progestins have been synthesized in the past decade, including dienogest, drospirenone, Nestorone, nomegestrol acetate and trimegestone. Drospirenone differs from the classic progestins in its derivation from spirolactone. The major effect of drospirenone is antimineralocorticoid activity. By that property, drospirenone causes decreased salt and water retention, and thus lowering of blood pressure. The affinity of drospirenone for the mineralocorticoid receptor is about five times that of aldosterone, the naturally occurring mineralocorticoid. In addition, drospirenone has no androgenic effect, but does exhibit partial antiandrogenic activity; its antiandrogenic potency is about 30% of that of cyproterone acetate, the progestin with the most potent antiandrogenic activity. This property, shared by several new progestins, may counteract the negative effect of androgens on hair growth, lipid changes, insulin and, possibly, body composition in postmenopausal women. Drospirenone has a long terminal half-life (about 32 hours), and its bioavailability is about 76%. Drospirenone, which has pharmacodynamic properties very similar to those of progesterone, has been developed as a combined oral contraceptive (30 microg ethinylestradiol/3 mg drospirenone; Yasmin, Schering AG, Berlin, Germany). Drospirenone is also available in combination with estradiol as an HRT preparation (1 mg 17beta-estradiol/2 mg drospirenone; Angeliq, Schering AG).

The risk of venous thromboembolism associated with the use of tranexamic acid and other drugs used to treat menorrhagia: a case-control study using the General Practice Research Database

OBJECTIVE

To assess whether use of tranexamic acid is associated with an increased risk of venous thromboembolism (VTE).

DESIGN

Nested case-control study.

SETTING

Database study using the General Practice Research Database for the years 1992-1998.

POPULATION

Women aged 15-49 years with a diagnosis of menorrhagia.

METHODS

Multivariate conditional logistic regression was used to estimate the risk for VTE associated with different drug treatments for menorrhagia, adjusting for confounders.

MAIN OUTCOME MEASURES

Adjusted odds ratios with 95% CI.

RESULTS

A total of 134 cases of VTE and 552 matched controls were identified. Recent use of tranexamic acid was scarce, yielding an adjusted odds ratio for VTE of 3.20 (95% CI 0.65-15.78). The use of mefenamic acid (ORadj 5.54 [95% CI 2.13-14.40]) or norethisterone (ORadj 2.41 [95% CI 1.00-5.78]) was associated with an increased risk of VTE, as was a recent--in relation to menorrhagia--diagnosis of anaemia or a haemoglobin value <11.5 g/dl (ORadj 2.23 [95% CI 1.02-4.86]).

CONCLUSIONS

We found that tranexamic acid was associated with an increased risk of VTE, although the risk estimate did not reach statistical significance. Increased risks of VTE associated with other treatments for menorrhagia were observed. The increased risk of VTE observed with a diagnosis of anaemia--a proxy for more severe menorrhagia--suggests that menorrhagia could be a prothrombotic condition. The observed association between VTE, tranexamic acid and other treatments for menorrhagia may thus partly be explained by confounding by indication. The possibility that menorrhagia is itself a risk factor for VTE merits further investigation.

Progesterone and its metabolite allopregnanolone differentially regulate hemostatic proteins after traumatic brain injury

Our laboratory has shown in numerous experiments that the neurosteroids progesterone (PROG) and allopregnanolone (ALLO) improve molecular and functional outcomes after traumatic brain injury (TBI). As coagulopathy is an important contributor to the secondary destruction of nervous tissue, we hypothesized that PROG and ALLO administration may also have a beneficial effect on coagulation protein expression after TBI. Adult male Sprague-Dawley rats were given bilateral contusions of the medial frontal cortex followed by treatments with PROG (16 mg/kg), ALLO (8 mg/kg), or vehicle (22.5% hydroxypropyl-beta-cyclodextrin). Controls received no injury or injections. Progesterone generally maintained procoagulant (thrombin, fibrinogen, and coagulation factor XIII), whereas ALLO increased anticoagulant protein expression (tissue-type plasminogen activator, tPA). In addition, PROG significantly increased the ratio of tPA bound to neuroserpin, a serine protease inhibitor that can reduce the activity of tPA. Our findings suggest that in a model of TBI, where blood loss may exacerbate injury, it may be preferable to treat patients with PROG, whereas it might be more appropriate to use ALLO as a treatment for thrombotic stroke, where a reduction in coagulation would be more beneficial.

Role of androgens, progestins and tibolone in the treatment of menopausal symptoms: a review of the clinical evidence

Estrogen-containing hormone therapy (HT) is the most widely prescribed and well-established treatment for menopausal symptoms. High quality evidence confirms that estrogen effectively treats hot flushes, night sweats and vaginal dryness. Progestins are combined with estrogen to prevent endometrial hyperplasia and are sometimes used alone for hot flushes, but are less effective than estrogen for this purpose. Data are conflicting regarding the role of androgens for improving libido and well-being. The synthetic steroid tibolone is widely used in Europe and Australasia and effectively treats hot flushes and vaginal dryness. Tibolone may improve libido more effectively than estrogen containing HT in some women. We summarize the data from studies addressing the efficacy, benefits, and risks of androgens, progestins and tibolone in the treatment of menopausal symptoms.

Novel perspectives for progesterone in hormone replacement therapy, with special reference to the nervous system

The utility and safety of postmenopausal hormone replacement therapy has recently been put into question by large clinical trials. Their outcome has been extensively commented upon, but discussions have mainly been limited to the effects of estrogens. In fact, progestagens are generally only considered with respect to their usefulness in preventing estrogen stimulation of uterine hyperplasia and malignancy. In addition, various risks have been attributed to progestagens and their omission from hormone replacement therapy has been considered, but this may underestimate their potential benefits and therapeutic promises. A major reason for the controversial reputation of progestagens is that they are generally considered as a single class. Moreover, the term progesterone is often used as a generic one for the different types of both natural and synthetic progestagens. This is not appropriate because natural progesterone has properties very distinct from the synthetic progestins. Within the nervous system, the neuroprotective and promyelinating effects of progesterone are promising, not only for preventing but also for reversing age-dependent changes and dysfunctions. There is indeed strong evidence that the aging nervous system remains at least to some extent sensitive to these beneficial effects of progesterone. The actions of progesterone in peripheral target tissues including breast, blood vessels, and bones are less well understood, but there is evidence for the beneficial effects of progesterone. The variety of signaling mechanisms of progesterone offers exciting possibilities for the development of more selective, efficient, and safe progestagens. The recognition that progesterone is synthesized by neurons and glial cells requires a reevaluation of hormonal aging.

Effects of oral and transvaginal ethinyl estradiol on hemostatic factors and hepatic proteins in a randomized, crossover study

CONTEXT

The use of combined hormonal contraceptives with ethinyl estradiol (EE) and a progestin results in alterations in potential biomarkers of venous thromboembolism risk. Evaluation of the impact of delivery route on these changes is difficult due to an interaction between EE and the progestin component.

OBJECTIVE

The aim of the study was to compare the impact of oral and vaginal administration of EE alone on hemostatic variables and estrogen-sensitive liver proteins.

DESIGN

This was a single-center, randomized, crossover study with two treatment cycles separated by a washout cycle.

SETTING

The study was conducted in an academic outpatient center.

PARTICIPANTS

Fourteen healthy postmenopausal women were enrolled; 13 completed the study and were included in the analyses.

INTERVENTION

Participants were randomized to receive EE (15 microg/d) delivered by oral tablet or vaginal ring for 21 d in one of two treatment sequences.

MAIN OUTCOME MEASURES

Changes in plasma concentration or activity of 10 hemostatic variables and six estrogen-sensitive liver proteins between baseline and d 21 of treatment were the primary outcomes.

RESULTS

Prothrombin fragment 1 + 2 plasma level was unaffected by treatment or delivery route. Angiotensinogen (expressed as plasma level of angiotensin I) increased similarly with oral and vaginal delivery; mean (sd) increases were 2757 (1033) and 2864 (893) ng /ml, respectively (P = 0.0002). Alterations in other study variables, except total cholesterol, were similar with oral and vaginal administration.

CONCLUSION

Our results provide evidence that the customary effects of combined hormonal contraceptives on hemostatic variables and estrogen-sensitive liver proteins are largely related to EE and independent of delivery route during short-term treatment.

Myocardial infarction with normal coronary arteries: a conundrum with multiple aetiologies and variable prognosis: an update

The existence of myocardial infarction despite angiographically normal coronary arteries was recognized more than 30 years ago. Since then, various series of such patients have been described, but the aetiology and pathogenesis of the condition are still a source of debate. Evidence exists for a role of coronary vasospasm, thrombosis, embolization and inflammation, per se or combined, in determining the occurrence of myocardial infarction in the presence of angiographically normal coronary arteries. Endothelial dysfunction, possibly superimposed to nonangiographically evident atherosclerosis, may be an underlying common feature predisposing to the acute event. Additionally, myocarditis may explain some of these occurrences. Myocardial infarction with normal coronary arteries is therefore likely the result of multiple pathogenetic mechanisms. Although most reports emphasize the good prognosis of this condition, in general much better than myocardial infarction with coronary artery disease, prognosis is likely variable according to the underlying mechanism. This review summarizes current knowledge on this condition and examines areas of recent progress.

Estrogen receptor 1 haplotype does not regulate oral contraceptive-induced changes in haemostasis and inflammation risk factors for venous and arterial thrombosis

BACKGROUND

Administration of oral contraceptives (OCs) has profound effects on the plasma levels of haemostasis and inflammation variables, resulting in an increased thrombosis risk. Individuals show large differences in the response of these variables to OCs. Polymorphism in the estrogen receptor-1 (ER1) gene may explain part of this inter-individual response.

METHODS

We investigated the relationship between variants (c.454-397T>C and c.454-351A>G polymorphisms and the combined haplotype) in the ER1 gene in relation to changes in haemostasis and inflammation variables that are known risk factors for thrombosis in 507 healthy, nonsmoking, nulliparous women receiving six cycles of monophasic OCs with 20, 30 or 50 microg/day estrogen.

RESULTS

A significant relationship was observed between the ER1 haplotype and changes in tissue-type plasminogen activator activity (P = 0.006), but no clear interaction pattern between the genotypes or between the estrogen doses was seen. No relationships were observed for the other variables, neither in the haplotype nor in the single polymorphism analysis.

CONCLUSION

The ER1 haplotype does not have a strong effect on the estrogen-induced changes in haemostasis and inflammation risk markers for arterial and venous thrombosis.

Effect of a combined oral contraceptive containing 20 microg ethinyl estradiol and 75 microg gestodene on hemostatic parameters

The effects of a combined oral contraceptive (COC) containing 20 microg ethinyl estradiol (EE) and 75 microg gestodene (GSD) on prothrombin activity (PA), activated partial thromboplastin time (APTT), thrombin time (TT), platelet number, fibrinogen, antithrombin III (ATIII), protein C, protein S and D-dimer were evaluated over 6 months in 23 young, healthy women. Laboratory assessments were performed prior to initiation of COC use (pretreatment) and after 3 and 6 months of use. Results showed no significant changes in fibrinogen, protein C, ATIII or D-dimer during COC use, compared with pretreatment values. The increase in platelet count, decreases in protein S level, PA and APTT, and the prolongation of TT were significant. In conclusion, the use of a COC containing 20 microg EE and 75 microg GSD did not cause any significant changes in the hemostatic parameters studied that could be suggestive of a higher prothrombotic risk. Further studies with a larger sample size are necessary in order to obtain conclusive data.

Treatment of menopausal symptoms: what shall we do now?

During the past few years, many women and doctors have revised their opinions of hormone replacement therapy (HRT) for menopausal symptoms, and a substantial number of individuals have discontinued its use because of concerns about side-effects. Numerous alternatives to HRT are promoted, and assessment of the quality of evidence about the safety and effectiveness of these compounds can be difficult. In this Review, we summarise the data from studies addressing the efficacy, risks, and benefits of frequently prescribed treatments, and offer evidence-based clinical guidelines for the management of menopausal symptoms. Although few comparative studies exist, oestrogen alone or combinations of oestrogen and progestagen are likely to be the most effective treatments for menopausal hot flushes and vaginal dryness. Tibolone is as effective as HRT, however, and might also improve libido. For those who wish to avoid hormonal treatments, there are few effective options. Selective serotonin reuptake inhibitors might be effective in the very short term (less than 12 weeks) and are well tolerated. There is not enough evidence that any of the complementary therapies available are any better than placebo for menopausal vasomotor symptoms, and few safety data exist.