Progestin-only contraception and venous thromboembolism

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.

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.

Combined Oral Contraceptives and Venous Thromboembolism: Review and Perspective to Mitigate the Risk

Many factors must be considered and discussed with women when initiating a contraceptive method and the risk of venous thromboembolism (VTE) is one of them. In this review, we discuss the numerous strategies that have been implemented to reduce the thrombotic risk associated with combined oral contraceptives (COCs) from their arrival on the market until today. Evidences suggesting that COCs were associated with an increased risk of VTE appeared rapidly after their marketing. Identified as the main contributor of this risk, the dosage of the estrogen, i.e., ethinylestradiol (EE), was significantly reduced. New progestins were also synthetized (e.g., desogestrel or gestodene) but their weak androgenic activity did not permit to counterbalance the effect of EE as did the initial progestins such as levonorgestrel. Numerous studies assessed the impact of estroprogestative combinations on hemostasis and demonstrated that women under COC suffered from resistance towards activated protein C (APC). Subsequently, the European Medicines Agency updated its guidelines on clinical investigation of steroid contraceptives in which they recommended to assess this biological marker. In 2009, estradiol-containing COCs were marketed and the use of this natural form of estrogen was found to exert a weaker effect on the synthesis of hepatic proteins compared to EE. In this year 2021, a novel COC based on a native estrogen, i.e., estetrol, will be introduced on the market. Associated with drospirenone, this preparation demonstrated minor effects on coagulation proteins as compared with other drospirenone-containing COCs. At the present time, the standard of care when starting a contraception, consists of identifying the presence of hereditary thrombophilia solely on the basis of familial history of VTE. This strategy has however been reported as poorly predictive of hereditary thrombophilia. One rationale and affordable perspective which has already been considered in the past could be the implementation of a baseline screening of the prothrombotic state to provide health care professionals with objective data to support the prescription of the more appropriate contraceptive method. While this strategy was judged too expensive due to limited laboratory solutions, the endogenous thrombin potential-based APC resistance assay could now represent an interesting alternative.

Oral Contraceptives and Venous Thromboembolism: Focus on Testing that May Enable Prediction and Assessment of the Risk

Combined oral contraceptives (COCs) induce several changes in the levels of coagulation factors. The levels of procoagulant factors are often increased, while levels of anticoagulant factors are decreased. Fibrinolysis is also affected, even if the effect seems to be more counterbalanced by opposite regulation of profibrinolytic and antifibrinolytic factors. These effects on hemostasis are more pronounced with third- or fourth-generation COC compared with second-generation COC. Venous thromboembolism (VTE) risk increases when multiple risk factors, including genetic and environmental, are present simultaneously. COC use causes changes in coagulation that modify the prothrombotic state induced by preexisting hemostatic alterations in a supra-additive manner. Therefore, testing appears to be of importance not only before implementing COC but also to monitor any potential thrombogenicity induced by COC therapy. Inherited genetic factors, such as factor V Leiden, G20210A prothrombin mutation, antithrombin, protein C or protein S deficiencies, non-O blood group, as well as CYP2C9*2 and the rs4379368 mutations, have all been identified as genetic predictive risk factors of VTE in women. Nevertheless, the screening of these genetic biomarkers is not capable of assessing the phenotypic expression of the risk. This review will focus on the different options for screening the thrombogenic status in this population. Specific attention will be given to the endogenous thrombin potential-based activated protein C resistance, a test aiming at assessing the thrombogenicity induced by hormonal therapies and inherited or acquired thrombophilia.

A systematic review and meta-analysis of venous thrombosis risk among users of combined oral contraception

Background

Combined oral contraceptives (COCs) containing various progestogens could be associated with differential risks for venous thromboembolism (VTE).

Objective

To evaluate the comparative risks of VTE associated with the use of low‐dose (less than 50 μg ethinyl estradiol) COCs containing different progestogens.

Search strategy

PubMed and the Cochrane Library were searched from database inception through September 15, 2016, by combining search terms for oral contraception and venous thrombosis.

Selection criteria

Studies reporting VTE risk estimates among healthy users of progestogen‐containing low‐dose COCs were included.

Data collection and analysis

A random‐effects model was used to generate pooled adjusted risk ratios and 95% confidence intervals; subgroup and sensitivity analyses assessed the impact of monophasic‐COC use and study‐level characteristics.

Main results

There were 22 articles included in the analysis. The use of COCs containing cyproterone acetate, desogestrel, drospirenone, or gestodene was associated with a significantly increased risk of VTE compared with the use of levonorgestrel‐containing COCs (pooled risk ratios 1.5–2.0). The analysis restricted to monophasic COC formulations with 30 μg of ethinyl estradiol yielded similar findings. After adjustment for study characteristics, the risk estimates were slightly attenuated.

Conclusions

Compared with the use of levonorgestrel‐containing COCs, the use of COCs containing other progestogens could be associated with a small increase in risk for VTE.

Combined oral contraceptives containing certain progestogens could be associated with a small increase in risk for venous thromboembolism compared with those containing levonorgestrel.

Effect of Progesterone and Synthetic Progestins on Whole Blood Clot Formation and Erythrocyte Structure

Combined oral contraceptive (COC) use is a risk factor for venous thrombosis (VT) and related to the specific type of progestin used. VT is accompanied by inflammation and pathophysiological clot formation, that includes aberrant erythrocytes and fibrin(ogen) interactions. In this paper, we aim to determine the influence of progesterone and different synthetic progestins found in COCs on the viscoelasticity of whole blood clots, as well as erythrocyte morphology and membrane ultrastructure, in an in vitro laboratory study. Thromboelastography (TEG), light microscopy, and scanning electron microscopy were our chosen methods. Our results point out that progestins influence the rate of whole blood clot formation. Alterations to erythrocyte morphology and membrane ultrastructure suggest the presence of eryptosis. We also note increased rouleaux formation, erythrocyte aggregation, and spontaneous fibrin formation in whole blood which may explain the increased risk of VT associated with COC use. Although not all COC users will experience a thrombotic event, individuals with a thrombotic predisposition, due to inflammatory or hematological illness, should be closely monitored to prevent pathological thrombosis.

Risks of thromboembolism associated with hormone contraceptives in Japanese compared with Western women

We extracted 581 thromboembolic events associated with combined oral contraceptives (COC) that occurred between 2004 and 2013 in Japan, from the Pharmaceuticals and Medical Devices Agency database. The most common thromboembolic events associated with COC were deep vein thrombosis, pulmonary embolism and their combination. The reported thromboembolic events increased year by year, in association with an increase in the quantity of prescribed low-dose estrogen progestin after approval for health insurance coverage for dysmenorrhea in 2008 in Japan. The incidence of venous thromboembolism (VTE) in Japanese COC users is estimated to be lower compared with their Western counterparts. In contrast, the frequency of all thromboembolic events peaked at 90 days from the start of COC, as in Western studies. The risk of VTE in the overweight group (body mass index ≥ 25 kg/m² ) was more than twofold higher than in the standard group, and age-specific incidence rate rose sharply after the age of 40. There were different VTE risks according to progestin type in Japan as in Western countries, but a definite conclusion about risk according to progestin type was not able to be reached at present. As for the risk of arterial embolism and thrombosis, the difference by progestin type was small, but it became higher at ≥50 years of age. Last, mortality rate caused by thromboembolism is extremely low among COC users.

Progestin-only contraception and thromboembolism: A systematic review

BACKGROUND

Women with medical conditions associated with increased risk for thrombosis generally should not use estrogen-containing contraceptives; however, less is known about progestin-only contraceptives (POCs) and thrombosis risk.

OBJECTIVES

The objective was to identify evidence regarding the risk of venous thromboembolism (VTE) or arterial thromboembolism [stroke or acute myocardial infarction (AMI)] among women using POCs.

METHODS

We searched the PubMed database for all articles published from database inception through January 2016 for studies examining thrombosis among women using POCs. We included studies which examined women with medical conditions associated with thrombosis risk, as well as studies of women in the general population (either without these conditions or who were not specified to have these conditions). Hormonal contraceptives of interest included progestin-only pills (POPs), injectables, implants and levonorgestrel-releasing intrauterine devices (LNG-IUDs). Outcomes of interest included VTE, stroke and AMI.

RESULTS

There were 26 articles of good to poor quality that met inclusion criteria; 9 studies examined women with medical conditions and 20 examined women in the general population. Two studies found that, among smokers and women with certain thrombogenic mutations, use of depot medroxyprogesterone acetate (DMPA) had elevated odds of VTE compared with nonsmokers or those without mutations, although confidence intervals were wide and overlapped with odds among nonusers. One study found that, among women with previous VTE, use of POCs (including DMPA) was associated with a nonsignificant increased odds of recurrent VTE (all of which were among DMPA users); two other studies that examined POCs other than DMPA did not observe an association with recurrent VTE. Two studies found that use of DMPA among healthy women was also associated with increased odds of VTE. Two studies found that use of POCs for therapeutic indications was associated with increased odds of VTE. Studies did not find increased odds of VTE with POPs for contraceptive purposes, implants or LNG-IUDs nor were there increased odds of stroke or AMI with any POCs.

CONCLUSION

The majority of evidence identified by this systematic review did not suggest an increase in odds for venous or arterial events with use of most POCs. Limited evidence suggested increased odds of VTE with use of injectables (three studies) and use of POCs for therapeutic indications (two studies, one with POCs unspecified and the other with POPs). Any increase in risk likely translates to a small increase in absolute numbers of thrombotic events at the population level.

Canadian Contraception Consensus (Part 3 of 4): Chapter 8 - Progestin-Only 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, ease of use, and side effects; the effect of cited contraceptive methods on sexual health and general well-being; and the relative cost and availability of cited contraceptive methods in Canada.

EVIDENCE

Published literature was retrieved through searches of Medline and The Cochrane Database from January 1994 to January 2015 using appropriate controlled vocabulary (e.g., contraception, sexuality, sexual health) and key words (e.g., contraception, family planning, hormonal contraception, emergency contraception). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English from January 1994 to January 2015. Searches were updated on a regular basis in incorporated in the guideline to June 2015. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of the evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). CHAPTER 8: PROGESTIN-ONLY CONTRACEPTION: Summary Statements Recommendations.

Drospirenone detected in postmortem blood of a young woman with pulmonary thromboembolism: A case report and review of the literature

Progestin/estrogen oral contraceptives have some side effects, including venous thromboembolism. To alleviate side effects, improvements have been made to low-dose oral contraceptives, including reductions in the amount of estrogen and/or changes the type of progestin. A compound drug containing 3mg drospirenone and 20μg ethinylestradiol (DRSP/EE20, YAZ®) was released in overseas markets in 2006, and in Japan in 2010 as a newly developed low-dose medicines. This drug is expected to have lower side effects. We received a medicolegal autopsy case of a young woman who had been prescribed YAZ for dysmenorrhea for 17months. The autopsy revealed a blood clot in her pulmonary artery bifurcation. Blood screening by ultra-performance liquid chromatography-mass spectrometry analysis did not detect any medicinal toxicants. However, from police investigations, it is strongly believed that she had been taking YAZ. Therefore we performed a single ion resolution mode assay and detected DRSP. A quantitative analysis revealed 32.3ng/mL of DRSP. As no other cause of the pulmonary thromboembolism was evident, we consider YAZ as the likely cause of the pulmonary thromboembolism. Recent reports from the past few years suggest a higher risk of venous thromboembolism with DRSP/EE20 than earlier progestin/estrogen oral contraceptives. Comparing the risk associated with DRSP/EE20 and DRSP/EE30, one report found no differences and another report showed DRSP/EE20 was associated with a higher risk than DRSP/EE30. No cases of thrombosis caused by progestin alone have been reported. But comparing the risk between DRSP/EE20 and other progestins/EE20, two studies reported DRSP/EE20 had a higher risk than other progestins/EE20. The incidence of venous thromboembolism is highest in the first year of use and decreases thereafter. Because DRSP/EE20 has been on the market for only a couple of years, it is necessary for clinicians to use the drug carefully and accumulate more side-effect data. It is important for forensic scientists to confirm all of the prescribed drugs in autopsy cases, search the risks of identified drugs, particularly new drugs, and provide relevant case information in a timely manner.

Usefulness of progesterone-only components for contraception in patients with congenital heart disease

The objective of the study is to report the contraceptive methods used by patients with congenital heart disease (CHD) before referral to a specific preconception clinic and evaluate safety and treatment adherence of the alternative contraception method, progesterone-only component (PC), offered. Contraceptive methods in the CHD population reported included estrogen-progesterone combined contraceptives (EPCC), despite the potential risk for thromboembolism. PC has been suggested as an alternative, but, no information on its use has been reported. Retrospective analysis was performed of all patients (n = 237) referred to the preconception clinic of an adult CHD center. Thirty-three percent of patients had used EPCC in the past; 3.8% had had thromboembolic events during its use. Current contraception consisted of barrier methods in 58% of patients, EPCC in 18%, and PC in 1.3%; 21.7% of patients were not using any contraception. PC was offered as an alternative in 146 patients; 73% of patients agreed to start the treatment. At a median follow-up of 1 year, 73% of patients who started PC maintained the treatment. Gynecologic side effects were reported in 25% of patients, with no cardiovascular effects. In conclusion, a significant proportion of patients with CHD were former users of EPCC, although some had formal contraindications, and the rate of PC use before referral to the preconception clinic was low. After being offered as an alternative treatment, the use of PC in its various forms was extensive, with no thrombogenic side effects and an acceptable rate of gynecologic side effects being reported.

Hormonal contraceptives and venous thromboembolism: an epidemiological update

Since the early 1960s, it has been well documented that combined hormonal contraceptives increase the risk of cardiovascular disease. Newer generation of oral formulations, as well as non-oral contraceptives (transdermal and vaginal), have been recently studied for thrombotic risk. This review provides a summary of the association between hormonal contraceptives and venous thromboembolism with emphasis on new formulations of hormonal contraceptives as well as route of administration. A systematic search of Medline database was done for all relevant articles which included women having used third generation pills, and the development of new progestins. Eligible articles published in English and reporting the risk of venous thromboembolism (VTE) (pulmonary embolism or deep venous thrombosis) among users of hormonal contraceptives were reviewed. A quantitative assessment was made from included studies. Current use of drospirenone or cyproterone oral combined contraceptives increased the risk of VTE compared with second generation pills (pooled OR: 1.7; 95% confidence interval [95% CI]: 1.4-2.2 and OR: 1.8; 95% CI: 1.4-2.3, respectively). In the context of contraceptive use, non-oral route of ethinyl-estradiol administration seems to be more thrombogenic than oral route. In contrast, low doses of both oral progestin contraceptives and intrauterine levonorgestrel could be safe with respect to VTE risk. In conclusion, newer generation formulations of hormonal contraceptives, as well as the non-oral hormonal contraceptive, seem to be more thrombogenic than second generation hormonal contraceptives.