The increased risk of venous thromboembolism and the use of third generation progestagens: role of bias in observational research. The Transnational Research Group on Oral Contraceptives and the Health of Young Women

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.

Systematic Review of Hormonal Contraception and Risk of Venous Thrombosis

Background

Hormonal contraception (HC) is widely used throughout the world and has been associated with venous thrombosis (VT) such as deep vein thrombosis, pulmonary emboli, and cerebral VT.

Objectives

To provide a current comprehensive overview of the risk of objectively confirmed VT with HC in healthy women compared to nonusers.

Search methods

PubMed was searched from inception to April 2018 for eligible studies in the English language, with hand searching from past systematic reviews.

Selection criteria

We selected original research evaluating risk of objectively confirmed VT in healthy women taking oral or nonoral HC compared with nonusers.

Data collection

The primary outcome of interest was a fatal or nonfatal VT in users of HC compared to nonusers or past users. Studies with at least twenty events were eligible. Adjusted relative risks with 95 percent confidence intervals were reported. Three independent reviewers extracted data from selected studies.

Results

1,962 publications were retrieved through the search strategy, with 15 publications included. Users of oral contraception with levonorgesterol had increased risk of VT by a range of 2.79-4.07, while other oral hormonal preparations increased risk by 4.0-48.6. Levonorgestrel intrauterine devices did not increase risk. Etonogestrel/ethinyl estradiol vaginal rings increased the risk of VT by 6.5. Norelgestromin/ethinyl estradiol patches increased risk of VT by 7.9. Etonogestrel subcutaneous implants by 1.4 and depot-medroxyprogesterone by 3.6. The risk of fatal VT was increased in women aged fifteen to twenty-four by 18.8-fold.

Conclusion

Users of HC have a significant increased risk of VT compared to nonusers. Current risks would project at least 300-400 healthy young women dying yearly in the United States due to HC. Women should be informed of these risks and offered education in fertility-awareness-based methods with comparable efficacy for family planning.

Summary

HC is widely used throughout the world and has been associated with blood clots in the legs and lungs. We searched the literature and found the risks of currently used forms of birth control increased between three- and ninefold for blood clots for healthy women. The risks found would project 300-400 women dying from using HC each year in the United States.

[Hormonal contraception and vascular risk: CNGOF Contraception Guidelines]

Venous thromboembolism and arterial ischemic events are the main deleterious diseases associated with the use of combined hormonal contraceptives (CHC). Even though their composition has been substantially improved, the vascular risk persists with the most recent CHCs use. If the vascular risk associated with CHCs containing 50μg EE is significantly higher than with those containing less than 50μg, there is no evidence that the CHCs containing either 30 or 20μg of EE induce different venous risks. CHC containing gestodene, desogestrel, drospirenone or cyproterone acetate are associated with a higher risk of venous thrombosis compared with levonorgestrel-containing CHCs. CHC containing norgestimate are associated with similar venous thrombosis risk than CHC containing levonorgestrel. Venous thrombosis risk of non-oral routes of administration of CHC appears to be equivalent to the risk of CHC containing gestodene or desogestrel, but this result is based on a small number of epidemiological studies. Before prescribing a CHC, it is important to determine all vascular risk factors. Family history of ischemic arterial event or venous thromboembolism disease should be routinely sought before any CHC prescription. All CHCs are contraindicated in women with biological thrombophilia, in women with combined vascular risk factors, in women with first-degree family history of arterial or venous event (under age 50) as well as in women suffering of migraine with aura. Progestin-only contraceptives are not associated with vascular risk (arterial or venous) outside of medroxyprogesterone acetate. In women with higher vascular risk, progestin-only contraceptives (administered by oral, sous-cutaneous or intra-uterine routes) can be prescribed.

The synthetic progestin, gestodene, affects functional biomarkers in neonatal rat osteoblasts through an estrogen receptor-related mechanism of action

BACKGROUND

Clinical studies have shown that gestodene (GDN), a potent third-generation synthetic progestin, affects bone resorption. However, its mode of action in bone cells is not fully understood. The aim of this study was to establish whether GDN affects bone directly or through its bioconversion to other metabolites with different biological activities.

METHODS

In this study, we investigated the effects of GDN and its A-ring reduced metabolites on proliferation, differentiation, and mineralization of calvarial osteoblasts isolated from neonatal rat and their capacity to displace [³H]-E₂ at ER binding sites.

RESULTS

In contrast to progesterone, gestodene did exert significant effects on osteoblast activities. The most striking finding was the observation that the A-ring reduced derivatives 3β,5α-tetrahydro-GDN and 3α,5α-tetrahydro-GDN, though to a lesser extent, had greater stimulatory effects on the osteoblast activity than those observed with GDN. The effects on osteoblast proliferation and differentiation induced by GDN-reduced derivatives were abolished by the antiestrogen ICI 182780, consistent with their binding affinities for the estrogen receptor. In addition, the presence of a 5α-reductase inhibitor or inhibitors of aldo-keto hydroxysteroid dehydrogenases abolished the GDN-induced enhancement of osteoblast differentiation. These results indicated that GDN is metabolized to the A-ring reduced metabolites with estrogen-like activities and through this mechanism, GDN may affect the osteoblast activity.

CONCLUSION

Together, the data suggest that synthetic progestins derived from 19-nortestosterone such as GDN, have beneficial effects on bone due to their biotransformation into metabolites with intrinsic estrogenic activity.

Oral Contraceptives and HRT Risk of Thrombosis

Estrogen-containing medication, prescribed either for contraception in women of reproductive age or for prevention of cardiovascular events and osteoporosis as well as for alleviation of symptoms related to menopause, is associated with changes in the hemostatic balance and contributes to increased risk of development of venous thromboembolic complications. This risk is dose and medication dependent, increases with age, congenital and/or acquired predisposition to thrombosis, and mode of administration. This review attempts to summarize the current knowledge regarding the pathophysiology of oral contraceptive (OC) and hormone replacement therapy (HRT) -induced prothrombotic state in women, the risk of thrombosis associated with administration of various commercially available OCs and HRT, the additional risk in women with hereditary or acquired thrombophilia, and the currently available recommendations regarding massive screening of women for thrombophilia prior to initial prescription or continuation of treatment with OCs and HRT preparations.

Combined hormonal contraception and the risk of venous thromboembolism: a guideline

While venous thromboembolism (VTE) is rare in young women of reproductive age, combined oral contraceptives increase the risk of VTE. In the patient in whom combined hormonal contraception is appropriate, it is reasonable to use any currently available preparation.

Does the Progestogen Used in Combined Hormonal Contraception Affect Venous Thrombosis Risk?

Combined hormonal contraceptives (CHCs) use a combination of estrogen and progestogen to provide contraception. The most important risk of using CHCs is venous thromboembolism (VTE). It is unclear whether the type of progestogen used in a method augments that risk. Although the evidence supporting an increase in thrombosis risk is not conclusive, neither is the evidence supporting the benefit of newer progestogens in terms of tolerability or continuation. The benefits of CHCs outweigh the risks and the absolute risk of VTE remains small. A balanced discussion of potential risks and benefits of particular CHC formulations is warranted during contraception counseling.

Use of combined oral contraceptives and risk of venous thromboembolism: nested case-control studies using the QResearch and CPRD databases

OBJECTIVE

To investigate the association between use of combined oral contraceptives and risk of venous thromboembolism, taking the type of progestogen into account.

DESIGN

Two nested case-control studies.

SETTING

General practices in the United Kingdom contributing to the Clinical Practice Research Datalink (CPRD; 618 practices) and QResearch primary care database (722 practices).

PARTICIPANTS

Women aged 15-49 years with a first diagnosis of venous thromboembolism in 2001-13, each matched with up to five controls by age, practice, and calendar year.

MAIN OUTCOME MEASURES

Odds ratios for incident venous thromboembolism and use of combined oral contraceptives in the previous year, adjusted for smoking status, alcohol consumption, ethnic group, body mass index, comorbidities, and other contraceptive drugs. Results were combined across the two datasets.

RESULTS

5062 cases of venous thromboembolism from CPRD and 5500 from QResearch were analysed. Current exposure to any combined oral contraceptive was associated with an increased risk of venous thromboembolism (adjusted odds ratio 2.97, 95% confidence interval 2.78 to 3.17) compared with no exposure in the previous year. Corresponding risks associated with current exposure to desogestrel (4.28, 3.66 to 5.01), gestodene (3.64, 3.00 to 4.43), drospirenone (4.12, 3.43 to 4.96), and cyproterone (4.27, 3.57 to 5.11) were significantly higher than those for second generation contraceptives levonorgestrel (2.38, 2.18 to 2.59) and norethisterone (2.56, 2.15 to 3.06), and for norgestimate (2.53, 2.17 to 2.96). The number of extra cases of venous thromboembolism per year per 10,000 treated women was lowest for levonorgestrel (6, 95% confidence interval 5 to 7) and norgestimate (6, 5 to 8), and highest for desogestrel (14, 11 to 17) and cyproterone (14, 11 to 17).

CONCLUSIONS

In these population based, case-control studies using two large primary care databases, risks of venous thromboembolism associated with combined oral contraceptives were, with the exception of norgestimate, higher for newer drug preparations than for second generation drugs.

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.

Epidemiology of hormonal contraceptives-related venous thromboembolism

For many years, it has been well documented that combined hormonal contraceptives increase the risk of venous thromboembolism (VTE). The third-generation pill use (desogestrel or gestodene (GSD)) is associated with an increased VTE risk as compared with second-generation (levonorgestrel) pill use. Other progestins such as drospirenone or cyproterone acetate combined with ethinyl-estradiol (EE) have been investigated. Most studies have reported a significant increased VTE risk among users of these combined oral contraceptives (COCs) when compared with users of second-generation pills. Non-oral combined hormonal contraception, such as the transdermal patch and the vaginal ring, is also available. Current data support that these routes of administration are more thrombogenic than second-generation pills. These results are consistent with the biological evidence of coagulation activation. Overall, the estrogenic potency of each hormonal contraceptive depending on both EE doses and progestin molecule explains the level of thrombotic risk. Some studies have shown a similar increased VTE risk among users of COCs containing norgestimate (NGM) as compared with users of second-generation pill. However, for this combination, biological data, based on quantitative assessment of sex hormone-binding globulin or haemostasis parameters, are not in agreement with these epidemiological results. Similarly, the VTE risk associated with low doses of EE and GSD is not biologically plausible. In conclusion, newer generation formulations of hormonal contraceptives as well as non-oral hormonal contraceptives seem to be more thrombogenic than second-generation hormonal contraceptives. Further studies are needed to conclude on the combinations containing NGM or low doses of EE associated with GSD.

Combined oral contraceptives: venous thrombosis

BACKGROUND

Combined oral contraceptive (COC) use has been associated with venous thrombosis (VT) (i.e., deep venous thrombosis and pulmonary embolism). The VT risk has been evaluated for many estrogen doses and progestagen types contained in COC but no comprehensive comparison involving commonly used COC is available.

OBJECTIVES

To provide a comprehensive overview of the risk of venous thrombosis in women using different combined oral contraceptives.

SEARCH METHODS

Electronic databases (Pubmed, Embase, Web of Science, Cochrane, CINAHL, Academic Search Premier and ScienceDirect) were searched in 22 April 2013 for eligible studies, without language restrictions.

SELECTION CRITERIA

We selected studies including healthy women taking COC with VT as outcome.

DATA COLLECTION AND ANALYSIS

The primary outcome of interest was a fatal or non-fatal first event of venous thrombosis with the main focus on deep venous thrombosis or pulmonary embolism. Publications with at least 10 events in total were eligible. The network meta-analysis was performed using an extension of frequentist random effects models for mixed multiple treatment comparisons. Unadjusted relative risks with 95% confidence intervals were reported.Two independent reviewers extracted data from selected studies.

MAIN RESULTS

3110 publications were retrieved through a search strategy; 25 publications reporting on 26 studies were included. Incidence of venous thrombosis in non-users from two included cohorts was 0.19 and 0.37 per 1 000 person years, in line with previously reported incidences of 0,16 per 1 000 person years. Use of combined oral contraceptives increased the risk of venous thrombosis compared with non-use (relative risk 3.5, 95% confidence interval 2.9 to 4.3). The relative risk of venous thrombosis for combined oral contraceptives with 30-35 μg ethinylestradiol and gestodene, desogestrel, cyproterone acetate, or drospirenone were similar and about 50-80% higher than for combined oral contraceptives with levonorgestrel. A dose related effect of ethinylestradiol was observed for gestodene, desogestrel, and levonorgestrel, with higher doses being associated with higher thrombosis risk.

AUTHORS' CONCLUSIONS

All combined oral contraceptives investigated in this analysis were associated with an increased risk of venous thrombosis. The effect size depended both on the progestogen used and the dose of ethinylestradiol. Risk of venous thrombosis for combined oral contraceptives with 30-35 μg ethinylestradiol and gestodene, desogestrel, cyproterone acetate and drospirenone were similar, and about 50-80% higher than with levonorgestrel. The combined oral contraceptive with the lowest possible dose of ethinylestradiol and good compliance should be prescribed-that is, 30 μg ethinylestradiol with levonorgestrel.

Different combined oral contraceptives and the risk of venous thrombosis: systematic review and network meta-analysis

OBJECTIVE

To provide a comprehensive overview of the risk of venous thrombosis in women using different combined oral contraceptives.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

PubMed, Embase, Web of Science, Cochrane, Cumulative Index to Nursing and Allied Health Literature, Academic Search Premier, and ScienceDirect up to 22 April 2013.

REVIEW METHODS

Observational studies that assessed the effect of combined oral contraceptives on venous thrombosis in healthy women. The primary outcome of interest was a fatal or non-fatal first event of venous thrombosis with the main focus on deep venous thrombosis or pulmonary embolism. Publications with at least 10 events in total were eligible. The network meta-analysis was performed using an extension of frequentist random effects models for mixed multiple treatment comparisons. Unadjusted relative risks with 95% confidence intervals were reported. The requirement for crude numbers did not allow adjustment for potential confounding variables.

RESULTS

3110 publications were retrieved through a search strategy; 25 publications reporting on 26 studies were included. Incidence of venous thrombosis in non-users from two included cohorts was 1.9 and 3.7 per 10,000 woman years, in line with previously reported incidences of 1-6 per 10,000 woman years. Use of combined oral contraceptives increased the risk of venous thrombosis compared with non-use (relative risk 3.5, 95% confidence interval 2.9 to 4.3). The relative risk of venous thrombosis for combined oral contraceptives with 30-35 µg ethinylestradiol and gestodene, desogestrel, cyproterone acetate, or drospirenone were similar and about 50-80% higher than for combined oral contraceptives with levonorgestrel. A dose related effect of ethinylestradiol was observed for gestodene, desogestrel, and levonorgestrel, with higher doses being associated with higher thrombosis risk.

CONCLUSION

All combined oral contraceptives investigated in this analysis were associated with an increased risk of venous thrombosis. The effect size depended both on the progestogen used and the dose of ethinylestradiol.

Drospirenone and non-fatal venous thromboembolism: is there a risk difference by dosage of ethinyl-estradiol?

BACKGROUND

Previous studies concluded that there was an increased risk of non-fatal venous thromboembolism (VTE) with drospirenone. It is unknown whether the risk is differential by ethinyl-estradiol dosage.

OBJECTIVES

To assess the risk of VTE with drospirenone and to determine whether drospirenone and ethinyl-estradiol 20 μg (DRSP/EE20) has a lower VTE risk than drospirenone and ethinyl-estradiol 30 μg (DRSP/EE30).

METHODS

Our cohort included women aged 18-46 years taking drospirenone or levonorgestrel (LNG)-containing combined oral contraceptives (COCs) in the IMS claims database between 2001 and 2009. VTE was defined using ICD-9-CM coding and anticoagulation. The hazard ratio (HR) from Cox proportional hazards models was used to assess the VTE relative risk (RR) with drospirenone compared with levonorgestrel, adjusted by a propensity score used to control for baseline co-morbidity and stratified by EE dosage and user-type (new/current).

RESULTS

The study included 238 683 drospirenone and 193,495 levonorgestrel users. Among new and current users, a 1.90-fold (95% CI, 1.51-2.39) increased VTE relative risk was observed for drospirenone (18.0 VTE/10,000 women-years) vs. levonorgestrel (8.9 VTE/10,000 women-years). In analysis of new users, DRSP/EE20 had a 2.35-fold (95% CI, 1.44-3.82) VTE RR versus LNG/EE20. New users of DRSP/EE30 observed an increased RR versus LNG/EE30 among women starting to use COCs between 2001 and 2006 (2.51, 95% CI, 1.12-5.64) but not between 2007 and 2009 (0.76, 95% CI, 0.42-1.39), attributable to an increased incidence rate with LNG/EE30 from 2007 to 2009. In direct comparison, DRSP/EE20 had an elevated risk of VTE compared with DRSP/EE30 (RR, 1.55; 95% CI, 0.99-2.41).

CONCLUSIONS

We observed a modestly elevated risk of VTE with drospirenone, compared with levonorgestrel. The larger VTE incidence rate observed in DRSP/EE20 than in DRSP/EE30 and the increasing VTE incidence rate with levonorgestrel between 2007 and 2009 were unexpected.

A pathway to improved prospective observational post-authorization safety studies

Randomized controlled trials (RCTs) are the gold standard for assessing the efficacy of drugs but not necessarily so for drug safety where inadequate power to detect either multiple or rare adverse events is a major handicap. Furthermore, the conditions under which drugs are approved for market use are often different from the settings in actual use. Indeed, with their control mechanisms, trials are by design largely inadequate for the identification of potential safety signals, especially of the rare type, hence the value of postmarketing surveillance and risk management plan-based activities. Today, clinical trials constitute only a part of the research that goes into assessing the safety of drugs. Observational studies, where the investigators merely collect data on treatments received by patients and their health status in routine clinical practice are increasing in uptake because they reflect the real-life utility of drugs, despite the absence of random treatment assignment. Although such studies generally provide less compelling evidence than RCTs, they can be far more useful to drug safety assessment activities than generally acknowledged. An increasing number of post-authorization safety studies (PASS) within the European Medicines Agency's jurisdiction are of the observational type - considered perhaps as more appropriate vehicles for exploring and documenting how products perform in the real world. A similar trend is emerging in the US following the FDA Amendments Act of 2007; since early 2010, an increasing number of post-approval commitments mandated by the FDA include observational studies. However, despite this pattern, not much is known about ongoing efforts to address many of the recognized inadequacies associated with existing methodologies and practices currently adopted in observational PASS. This current opinion presents an overview of some of the main challenges we face in prospective observational PASS, mainly from practical experience, and proposes certain steps for improvement.

Oral contraceptives and venous thromboembolism: a systematic review and meta-analysis

BACKGROUND

An association between oral contraceptive (OC) use and venous thromboembolism (VTE) has long been recognized. However, no summary estimates of the increase in VTE risk associated with OC use have been available since 1995, and no meta-analyses have evaluated the VTE risk of new preparations containing drospirenone.

OBJECTIVE

The aim of the study was to carry out a meta-analysis to summarize existing evidence on the association between venous VTE and OC use, and to investigate how such an association may vary according to the type of OC, OC user characteristics, study characteristics and biases.

METHODS

Relevant cohort or case-control studies were searched in MEDLINE and other electronic databases up to May 2010, with no language restriction. Data were combined using a generic inverse-variance approach. Meta-regression in addition to stratification was used to explore potential predictors of the summary estimate of risk.

RESULTS

Sixteen cohort and 39 case-control studies were included in at least one comparison. Overall, the odds ratio (OR) of OC users versus non-users was 3.41 (95% CI 2.98, 3.92). This estimate was based upon nine cohort studies evaluating approximately 12 000 000 person-years, and 23 case-control studies including approximately 45 000 women. VTE risk for OC users was significantly lower in studies evaluating 'all VTE cases' than in those evaluating 'idiopathic VTE only' (OR 3.09 and 4.94, respectively). Among the carriers of genetic mutations G20210A and Factor V Leiden (FVL), OC users showed a significantly increased VTE risk compared with non-users (OR 1.63; 95% CI 1.01, 2.65, and OR 1.80; 95% CI 1.20, 2.71, respectively). When the newest OCs containing drospirenone were compared with non-drospirenone-containing OCs (except those containing levonorgestrel only), VTE risk did not significantly increase (OR 1.13; 95% CI 0.94, 1.35).

CONCLUSIONS

This meta-analysis confirms that OC use significantly increases VTE risk. The strength of this association, however, varies according to the generation of OC, type of outcome and presence of a genetic mutation, with ORs ranging from 3 to 5.

A Bayesian semiparametric approach for incorporating longitudinal information on exposure history for inference in case-control studies

In a typical case-control study, exposure information is collected at a single time point for the cases and controls. However, case-control studies are often embedded in existing cohort studies containing a wealth of longitudinal exposure history about the participants. Recent medical studies have indicated that incorporating past exposure history, or a constructed summary measure of cumulative exposure derived from the past exposure history, when available, may lead to more precise and clinically meaningful estimates of the disease risk. In this article, we propose a flexible Bayesian semiparametric approach to model the longitudinal exposure profiles of the cases and controls and then use measures of cumulative exposure based on a weighted integral of this trajectory in the final disease risk model. The estimation is done via a joint likelihood. In the construction of the cumulative exposure summary, we introduce an influence function, a smooth function of time to characterize the association pattern of the exposure profile on the disease status with different time windows potentially having differential influence/weights. This enables us to analyze how the present disease status of a subject is influenced by his/her past exposure history conditional on the current ones. The joint likelihood formulation allows us to properly account for uncertainties associated with both stages of the estimation process in an integrated manner. Analysis is carried out in a hierarchical Bayesian framework using reversible jump Markov chain Monte Carlo algorithms. The proposed methodology is motivated by, and applied to a case-control study of prostate cancer where longitudinal biomarker information is available for the cases and controls.

Clinical profile of contraceptive progestins

The term progestogen has been widely utilized to indicate the general class of agents that includes both progesterone and its synthetic analogs, whereas the term progestin refers only to synthetic progestational steroids. The development of progestins has been influenced in a major way by the search for orally active hormonal contraceptives, since it is likely that hormonal contraceptives will continue to utilize a progestin, the only possible alternative being represented by the utilization of antiprogestins. Synthetic progestogens in clinical use today belong to three main chemical families: progesterone derivatives (progesterone, retro-progesterone, 19-norprogesterone and 17alpha-hydroxyprogesterone); gonane and 19-nortestosterone derivatives (norethisterone, levonorgestrel, desogestrel, gestodene, norgestimate); a spironolactone derivative. Biological potency of progestogens varies depending on the end-point measured, usually ovulation inhibition and endometrial transformation; with both these tests, the most active compounds are all gonane derivatives, with a potency over a 100 times that of the natural hormone. When administered in adequate doses, a progestin inhibits fertility by inhibiting ovulation. This action is mainly exerted at the hypothalamic level where, physiologically, progesterone decreases the number of LH pulses. When progestogens are delivered directly to the uterine cavity, their action seems to be purely local. It has been amply proven that--even when administered in doses that do not constantly inhibit ovulation--a progestin can still remain effective as a contraceptive by acting at the level of the cervical mucus and, at least in part, of the endometrium. Progestogens utilized today differ largely in their pharmacokinetics. In general, after intake, these compounds are rapidly absorbed and distributed so that peak serum concentrations are reached between 1 and 4 h. Third-generation progestins (desogestrel, gestodene, norgestimate) have common characteristics: a higher affinity for progesterone receptors than their predecessors, a lower affinity for androgen receptors, a higher selectivity of action, a higher central inhibitory activity, a higher potency at the level of the endometrium, and an overall metabolic neutrality, in terms of effects on lipid and carbohydrate metabolism. In general, progestins can induce two types of adverse effects: changes in lipid metabolism and bleeding irregularities. Whereas the newer compounds seem to have overcome the first of these adverse effects, the second remains untouched: to this day, proper cycle control can only be achieved with combined hormonal contraceptives.

Combined hormonal contraception and venous thromboembolism

This review provides an update of knowledge regarding venous thromboembolism (VTE) and combined hormonal contraceptives (CHCs) in the light of new progestins and new administration routes for CHCs. Practical recommendations are also offered. The association between the use of combined oral contraceptives (COCs) and an increased risk of VTE has been known about for many years, it being related mainly to the dose of oestrogen; however, recent research has also shown the influence of the type of progestin. When compared to COCs containing levonorgestrel or norethisterone, those containing desogestrel or gestodene present a two-fold greater risk of VTE; for COCs containing cyproterone acetate, the risk is four-fold greater, while there are no or insufficient data for those containing norgestimate, chlormadinone acetate or drospirenone. With regard to the contraceptive patch, the available data suggest that the risk of VTE is similar to that observed with COCs. There are no data concerning vaginal rings. The greatest risk of COC-associated VTE occurs during the first year of use, thus suggesting the existence of a predisposing condition, such as being a carrier of a thrombogenic mutation with which the COCs would exert a synergistic effect. Routine screening for such conditions is not justified. Changes in haemostatic variables produced by COCs, for example, acquired resistance to protein C, could be linked to VTE, although it has yet to be demonstrated that such alterations are related to a clinical risk of VTE among COC users. At present there are no laboratory tests able to detect an increased risk of VTE in asymptomatic women. The key procedures in terms of ensuring the safe use of this contraceptive method are a full clinical, personal and family history, in order to evaluate risk factors for VTE and cardiovascular disease, along with the recording of blood pressure and body mass index prior to the prescription of COCs.

Use of contraceptive methods by women with current venous thrombosis on anticoagulant therapy: a systematic review

BACKGROUND

As nearly all women with venous thromboembolism (VTE) will be treated with anticoagulant therapy, it is important to consider how anticoagulation affects the safety of contraceptive use.

STUDY DESIGN

We conducted a systematic review of the literature regarding use of contraceptive methods in women with current VTE on anticoagulant therapy. Due to the limited direct evidence that was identified, we expanded our search to include women on anticoagulant therapy for indications other than VTE and women with bleeding disorders.

RESULTS

Six articles met our inclusion criteria. Three observational studies found the levonorgestrel-releasing IUD (LNG-IUD) was an effective treatment for menorrhagia for women on anticoagulation therapy or with bleeding disorders. Prevention of recurrent hemorrhagic ovarian cysts was seen in women on chronic anticoagulation treated with depot-medroxyprogesterone acetate (DMPA) in one small observational study. Among women with bleeding disorders, no complications were seen in 16 women with placement of the LNG-IUD. One pharmacokinetic study found no statistically significant interaction between combined oral contraceptives and warfarin. Other than one case report, no evidence was found regarding the risk of recurrent thrombosis in women on anticoagulation therapy using a contraceptive method.

CONCLUSION

The majority of studies in this review examined treatment effects of the LNG-IUD or DMPA on complications of anticoagulation and found overall beneficial effects of their use in these circumstances. Minimal evidence in women with inherited bleeding disorders suggests that insertion of the LNG-IUD does not pose major bleeding risks in these women with appropriate management.

Hormone therapy and thromboembolic disease

PURPOSE OF REVIEW

Hormone therapy increases the risk of venous thromboembolism (VTE). To reduce this risk, changes in dosage, composition and route of administration have been made over the years. This review provides a summary of the available evidence and an update on the most recent findings on the issue.

RECENT FINDINGS

Contraceptives containing third-generation progestagens confer a higher risk of VTE than second-generation compounds. Little data are available on preparations containing less than 30 micarog of estrogen, new progestagens or levonorgestrel-releasing intrauterine devices. Hormone replacement therapy increases the risk of VTE by 2 to 3-fold. Transdermal administration may be less thrombogenic than oral administration, while different estrogens and progestagens may carry a different risk. VTE risk is further increased in carriers of inherited thrombophilia. Despite a similar increase in relative risk of thrombosis associated with hormone therapy, absolute risk is lower in fertile women and higher in postmenopausal ones. Universal screening for thrombophilia before prescribing hormone replacement therapy might be cost-effective.

SUMMARY

Careful evaluation of individual risk factor is warranted before prescribing hormone therapy. Further investigations are needed to establish whether or not newer compounds are safer than older ones with respect to the risk of thrombosis.

Prevention of venous thromboembolism in surgical patients with breast cancer

Background

No randomized trial has yet studied venous thromboembolism (VTE) prophylaxis in patients undergoing surgery for breast cancer.

Methods

Relevant articles were identified using Medline searches. Secondary articles were identified from the reference lists of key papers.

Results and conclusion

The absence of randomized trials comparing different methods of VTE prophylaxis with controls makes an evidence-based consensus among breast cancer surgeons difficult. Intermittent pneumatic compression (IPC) and graduated compression (GC) are effective in reducing VTE without the haemorrhagic complications associated with heparin; their effects are additive. The authors suggest the following strategy. All patients undergoing surgery for breast cancer should receive both IPC and GC, with heparin reserved for those at very high risk. A controlled trial should randomize women to receive heparin or not, and all women should have both IPC and GC. The primary endpoints should be the development of VTE and/or haemorrhagic complications.

Hormonal contraception in adolescents: special considerations

With the rates of unintended pregnancies in teenagers remaining high, it is crucial to present adolescents with all of the contraceptive options available to them. While barrier methods, for example, male condoms, are easily accessible and do not have adverse effects, their use must be consistent and correct with each act of intercourse. Hormonal contraception affords much better efficacy in preventing pregnancy when used with full compliance. Oral contraceptives are a popular method of contraception among adolescents and offer many non-contraceptive benefits along with the prevention of pregnancy. They have very few significant adverse effects, which are outweighed by the significant morbidity associated with teenage pregnancies, and can be used by most adolescent females. However, their minor bothersome effects do contribute to the high discontinuation rates seen. In addition, many girls find it difficult to remember to take a pill every day, leading to higher failure rates in teenagers than in adult women. The advent of long-acting, progestogen (progestin)-only methods, such as injectables and implantables, has been generally accepted by adolescents and these methods have proven to be more efficacious by avoiding the need for daily compliance. However, progestogen-only methods cause irregular bleeding and amenorrhea, which is not acceptable to many teenagers. In addition, the most widely used implant was taken off the market a few years ago and newer forms are not yet widely accessible. Other novel methods are currently available, including the transdermal patch and the vaginal ring. Both are combinations of estrogen and progestogen and have similar efficacy and adverse effect profiles to oral contraceptives. Their use may be associated with greater compliance by adolescents because they also do not require adherence to a daily regimen. However, there may be some drawbacks with these newer methods, for example, visibility of the patch and difficulty with insertion of the vaginal ring. When regular contraceptive modalities fail, emergency contraception is available. Choices include combination oral contraceptives, progestogen-only pills, mifepristone, or placement of a copper-releasing intrauterine device. These methods can be very useful for preventing pregnancy in adolescents as long as adolescents are aware of their existence and have easy access to them.

Venous thromboembolic disease in users of low-estrogen combined estrogen-progestin oral contraceptives

OBJECTIVE

To assess the relationship between venous thromboembolic disease (VTE) and use of low-estrogen dose (<50 microg) combined estrogen-progestin oral contraceptives (OC) and three thrombosis-related gene mutations in a United States population.

DESIGN

This case-control study was conducted in 1998-2000 among women ages 15-44 years who were members of the Kaiser Permanente Medical Care Program [KPMCP] (Northern and Southern California). Cases were women with incident VTE; about three times as many women frequency matched for age were randomly selected as controls from the KPMCP membership in the same years. Data were collected in a 1 h face-to-face interview; blood was drawn to extract DNA to test for gene polymorphisms. The analysis data set comprised 196 cases (mean age 35.3 years) and 746 controls (mean age 36.2 years).

RESULTS

The adjusted odds ratio (OR) for VTE associated with current OC use was 4.07 (95% confidence interval [CI]: 2.77-6.00). The OR associated with OC use was higher for women who were obese than in the nonobese (p = 0.01 for likelihood test for interaction) and in women without predisposing medical conditions (p = 0.02 for interaction). The adjusted OR for VTE was 7.10 (95% CI: 2.33-21.61) in women with factor V Leiden (G1691A) mutation, 2.83 (95% CI: 0.70-11.63) in women with prothrombin G20210A mutation and 0.26 (95% CI: 0.10-0.65) in women with the MTHFR C677T mutation. The OR for VTE in OC users with factor V Leiden mutation (11.32) was elevated more than in OC users without the mutation (3.20) and women with the mutation who were non-OC users (8.42), but confidence intervals overlapped.

CONCLUSIONS

The risk of VTE is increased in users of low-estrogen OC formulations. Obese women appear to be at greater risk of VTE when using OCs.

Safety concerns and health benefits associated with oral contraception

Since the introduction of hormonal contraceptives in the 1960s, there have been a variety of both health benefits and safety concerns attributed to their use. In most instances, the noncontraceptive benefits of oral contraceptives (OCs) outweigh the potential cardiovascular risks. In fact, the probability of a patient experiencing a cardiovascular event while taking a low-dose OC is very low. However, smoking, hypertension, obesity, and diabetes are risk factors that must be taken into account when prescribing OCs. The neoplastic effects of hormonal contraceptives have been extensively studied, and recent meta-analyses indicate that there is a reduction in the risk of endometrial and ovarian cancer, a possible small increase in the risk for breast and cervical cancer, and an increased risk of liver cancer. Finally, many women will experience noncontraceptive health benefits with OCs that expand far beyond pregnancy prevention. Some of these benefits include reduction in menstrual-related symptoms, fewer ectopic pregnancies, a possible increase in bone density, and possible protection against pelvic inflammatory disease.

Safety of a New Oral Contraceptive Containing Drospirenone

New chemical entities must undergo rigorous, and preferably independent, safety and efficacy assessments before entry into the market. This is also true for oral contraceptives (OCs) given their extensive usage by healthy women and the safety concerns highlighted by the so-called 'third generation pill scare' in Europe a decade ago. This scare heightened patient and physician awareness of the increased risk of thromboembolic complications (mainly venous thromboembolism [VTE]) associated with OC use. Yasmin (ethinylestradiol 30 microg/drospirenone 3 mg [EE/DRSP]) is a novel OC that was demonstrated in clinical phase I-III studies to be highly effective in preventing pregnancy and to have a good safety profile. Nonetheless, clinical trials are not usually sufficiently powered to detect rare adverse events such as VTE to enable comparison with other OCs, which could allay fears and concerns about their inherent risks. Therefore, an extensive assessment of the VTE risk associated with EE/DRSP has been undertaken by reviewing data from the clinical development programme, postmarketing surveillance and spontaneous worldwide reporting, as well as information from other sources. Spontaneous worldwide reporting has revealed a VTE reporting rate of 5.1/100 000 women-years with EE/DRSP use. In contrast, 3-year interim results from a large, controlled, prospective postmarketing surveillance study suggest a VTE rate of 61/100 000 women-years for EE/DRSP, which is similar to the rates of 60/100 000 and 73/100 000 women-years for levonorgestrel-containing OCs and other OCs, respectively. When placed in context with potential biases and confounding factors that would inflate the perceived risk of VTEs with a novel OC, the VTE rate with EE/DRSP does not highlight any safety concerns. Furthermore, the risk of VTE with EE/DRSP or other OCs is far less than that associated with pregnancy and delivery (up to 800/100 000 women-years) or than other risks of daily living. Available data indicate that EE/DRSP is not associated with any increased risk of other serious adverse events such as hyperkalaemia, cardiac arrhythmia or birth defects. Nonetheless, caution should be exerted in prescribing EE/DRSP to women with conditions that predispose to hyperkalaemia.Overall, the safety data with EE/DRSP and other OCs indicate that these products have no negative impact on the risk of VTE (and other adverse events) in women who receive OCs for contraception.

Estrogen-containing oral contraceptives are allowable in young women with factor V Leiden heterozygosity without a history of thrombosis

An 18-year-old woman without significant past medical and surgical history presents to discuss the safety and efficacy of oral contraceptives. She is sexually active and currently relying on condoms alone for birth control. Her cousin had a deep venous thrombosis (DVT) following a pregnancy. As part of the family screening, this patient was identified as a factor V Leiden heterozygote. The risks and benefits of initiating oral contraceptives are discussed.

FFPRHC Guidance (October 2003): First Prescription of Combined Oral Contraception

The Guidance provides information for clinicians on the steps to be taken before providing a woman with her first prescription for combined oral contraception. It updates and replaces previous Faculty Guidance. A key to the grades of recommendations, based on levels of evidence, is given at the end of this document. Details of the methods used by the Clinical Effectiveness Unit (CEU) in developing this Guidance, and evidence tables summarising the research basis of the recommendations, are available on the Faculty website (www.ffprhc.org.uk). Abbreviations used include: blood pressure (BP), body mass (BMI), bone mineral density (BMD), breakthrough bleeding (BTB), British National Formulary (BNF), combined oral contraception (COC), Committee on Safety of Medicines (CSM), confidence interval (CI), deep vein thrombosis (DVT), emergency contraception (EC), ethinyl oestradiol (EE), Faculty Aid to Continuing Professional Development Topics (FACT), Family Planning Association (fpa), follicule-stimulating homone (FSH), general practitioner (GP), intermenstrual bleeding (IMB), luteinising hormone (LT), microgram, myocardial infarction (MI), odds ratio (OR), oral contraception (OC), pulmonary embolism (PE), relative risk (RR), Scottish Intercollegiate Guideline Network (SIGN), sexually transmitted infection (STI), Summary of Product Characteristics (SPCs), venous thomboembolism (VTE), World Health Organization (WHO), WHO Medical Eligibility Criteria (WHOMEC), WHO Selected Practice Recommendations (WHOSPR).

Low-dose oral contraceptive effects on thromboelastogram criteria and relationship to hypercoagulability

OBJECTIVE

The study was undertaken to assess hypercoagulability, by using thromboelastography, in women who use low-dose oral contraceptives (OCs).

STUDY DESIGN

Forty-three women using low-dose OCs (<or=35 microg ethinyl estradiol) underwent thromboelastography before starting OCs and again during the third month of OC use. Prior and 3-month mean values of four thromboelastogram parameters (maximum amplitude [MA], K time, alpha angle, and R time) were compared by using paired t tests. Comparison according to progestin type was also performed with unpaired t tests.

RESULTS

Prior versus 3-month values for MA, alpha, and K were not significantly different (P values-K: 0.8; alpha:.34; MA: 0.49); power was adequate to detect small differences. The 3-month R time was decreased compared with pre-OC values (P =.025), although the magnitude of this change was not characteristic of hypercoagulability. Comparison according to progestin type demonstrated no difference.

CONCLUSION

We found no significant trend toward hypercoagulability in women who used low-dose OCs and who otherwise had no known thromboembolic risks.

Diagnostic studies for thrombophilia in women on hormonal therapy and during pregnancy, and in children

OBJECTIVE

To review the role of acquired and inherited prothrombotic risk factors that increase the risk of thrombosis in oral contraceptive users, during pregnancy, and in neonates, infants, and children; and to determine by the consensus opinion of recognized experts in the field which risk factors should be determined in which individuals at which time.

DATA SOURCES

Review of the medical literature and current clinical practice by a panel of experts in the field of thrombophilia.

DATA EXTRACTION AND SYNTHESIS

The experts made an extensive review of the published literature and prepared a draft manuscript, which included preliminary recommendations. The draft manuscript was circulated to participants in the College of American Pathologists Conference XXXVI: Diagnostic Issues in Thrombophilia prior to the conference. The manuscript and recommendations were then presented at the conference for discussion. Recommendations were accepted if a consensus of the 26 experts attending the conference was reached. The results of the discussion were used to revise the manuscript into its final form.

CONCLUSIONS

This report reviews the options for testing for thrombophilic states in women using oral contraceptives, during pregnancy, and in neonates and children. General guidelines for testing in these clinical situations are provided, along with citation of the appropriate supporting literature.

Laboratory evaluation of hypercoagulability with venous or arterial thrombosis

OBJECTIVE

To provide recommendations for hypercoagulation testing for patients with venous, arterial, or neurovascular thrombosis, as reflected in the medical literature and the consensus opinion of recognized experts in the field.

DATA SOURCES, EXTRACTION, AND SYNTHESIS

The authors extensively examined the literature and current practices, and prepared a draft manuscript with preliminary recommendations. The draft manuscript was circulated to each of the expert participants (n = 30) in the consensus conference prior to the convening of the conference. The manuscript and recommendations were then presented at the conference for discussion. Recommendations were accepted if a consensus of the 28 experts attending the conference was reached. The discussions were also used to revise the manuscript into its final form.

CONCLUSIONS

The resulting article provides 17 recommendations for hypercoagulation testing in the setting of venous, arterial, or neurovascular thrombosis. The supporting evidence for test selection is analyzed and cited, and consensus recommendations for test selection are presented. Issues for which a consensus was not reached at the conference are also discussed.

Risk factors for thromboembolism in teens: when should I test?

The discoveries of the factor V Leiden mutation and the prothrombin gene variant 20210 in the last decade have markedly contributed to the understanding of the molecular pathophysiology of inherited risk factors for thrombophilia. Population studies in the adult literature have shown that although the overall prevalence of these defects is low, affected individuals are at increased risk of thrombosis particularly if acquired risk factors for thrombosis are also present. The use of combined hormonal oral contraceptive pills is a well-known acquired risk factor, and recent studies have shown significant increased risk of thrombosis for women who carry the factor V Leiden mutation and use oral contraceptive pills. Despite this significant increased risk, mass screening of asymptomatic women for factor V Leiden prior to prescribing oral contraceptive pills is not a cost-effective use of health care dollars and could result in unnecessarily preventing many women from the contraceptive and noncontraceptive benefits of this medication. Instead, clinicians can use thoughtful screening questions to identify potentially high-risk patients for thrombophilia and consider testing for inherited risk factors on a case-specific basis.

Case-control studies on venous thromboembolism: bias due to design? A methodological study on venous thromboembolism and steroid hormone use

This study addressed methodological issues of epidemiologic studies on venous thromboembolism (VTE) to show how design decisions can affect the results. It examines the influence of a restricting to hospitalized and to "idiopathic" cases of VTE in case-control studies on VTE risk and oral contraceptive (OC) use and thereby the bias potential. The diagnostic processes and OC exposures of 1068 suspected cases of VTE were followed in 21 German centers from 1994 to 1999 and evaluated compared to population and hospital controls. Of 606 confirmed cases, 385 (65.5%) were hospitalized, 168 (27.7%) were "idiopathic." Comparing users versus nonusers of OCs, the odds ratio (OR) for VTE risk for all cases and controls was 3.38 and 5.44 for "idiopathic" VTE. For hospital cases and controls, the OR was 3.72 and 9.1 for "idiopathic" VTE. The risk ratio for third- vs. second-generation OCs was increased in the hospital base but not in the population base. It was concluded that restriction to hospitalized events and exclusions of certain cases overestimate the VTE risk of OCs. An evidence-based consensus on methodological standards and definitions in case-control studies on VTE and steroid hormone use is required.

Female hormones and thrombosis

Exogenous hormones are used by more than a hundred million women worldwide as oral contraceptives or for postmenopausal hormone replacement. Oral contraceptives increase the risk of venous thrombosis, of myocardial infarction, and of stroke. The risk is highest during the first year of use. The venous thrombotic risk of oral contraceptives is high among women with coagulation abnormalities and with so-called third-generation contraceptives (containing desogestrel or gestodene). The risk of myocardial infarction does not appear to depend on coagulation abnormalities or the type of oral contraceptive. Hormone replacement therapy increases the risk of venous thrombosis. This risk is also highest in the first year of use and among women with coagulation abnormalities. The risk becomes very high in women with a previous venous thrombosis. Randomized trials have not confirmed a beneficial effect of postmenopausal hormones on the occurrence of myocardial infarction.

Triphasic oral contraceptives: review and comparison of various regimens

OBJECTIVE

To review and compare the risk-benefit profile of triphasic oral contraceptives with that of low-dose monophasic oral contraceptives.

DESIGN

Literature on currently marketed triphasics and monophasics.

PATIENT(S)

Healthy women of reproductive age.

MAIN OUTCOME MEASURE(S)

Comparison of the rationale for development, composition, mechanism, efficacy, menstrual cycle control, side effects, health benefits, and risk-benefit profile.

RESULT(S)

All triphasics contain ethinyl estradiol (0.025-0.040 mg/d) and one of several progestins in doses (0.05-1.0 mg/d) related to their relative potencies, which are substantially lower overall (total dose) than those in monophasics. The triphasics are highly efficacious. In general, menstrual cycle control and side effects are similar in both types, but triphasics containing the newer progestins (desogestrel, gestodene, and norgestimate) have better cycle control and a reduced incidence of androgenic side effects compared with those with norethindrone or levonorgestrel. Both triphasics and monophasics have minimal effects on carbohydrate and lipid metabolism and hemostasis parameters, and therefore comparable low risks of coronary heart disease. The health benefits of triphasics and monophasics are similar and include decreased incidence of unwanted and ectopic pregnancies, ovarian cysts, endometrial and ovarian cancers, benign breast disease, and acute pelvic inflammatory disease; less menstrual blood loss and iron deficiency anemia; and lower frequency of irregular bleeding and menorrhagia.

CONCLUSION(S)

The risk-benefit profiles of both triphasics and monophasics are favorable and similar.

Third-generation progestogen type influences hemostatic changes caused by oral contraceptives in Brazilian women

We compared the effects of two third-generation progestogens, desogestrel (DSG) and gestodene (GSD), on coagulation and fibrinolysis in Brazilian users of oral contraceptives (OCs). Forty-six women were evaluated before treatment and after six cycles of treatment. The coagulation, anticoagulant, and fibrinolytic systems were investigated. During the use of the DSG-containing OC, the activity of factors VII, VIII, IX, X, and XII increased significantly whereas the GSD-containing OC caused no changes in coagulation parameters. Concerning the anticoagulant pathways, the DSG-containing OC increased protein C levels and decreased total protein S levels, and the GSD-containing OC only decreased total protein S. Both OCs increased plasminogen activity, although the DSG-containing OC increased fibrin degradation products levels and decreased the tissue plasminogen activator antigen. In conclusion, we have found that in Brazilian women the effects of DSG and GSD on hemostatic parameters are different and, therefore, third-generation progestogens may not contribute equally to the thrombotic risk.

Current perspectives on oral contraceptive use

Oral contraceptives are one of the most highly effective forms of contraception and provide many short- and long-term noncontraceptive health benefits. They control menstrual cycle irregularities, such as breakthrough bleeding and amenorrhea, and are effective in treating dysfunctional uterine bleeding. In addition, for decades after oral contraceptive use is discontinued they are associated with substantial decreases in the risk of ovarian cancer (up to 80%) and of endometrial cancer (40%-50%), and nearly eliminate benign functional ovarian cysts. Long-term oral contraceptive use confers protection against benign breast disease and colorectal cancer, may help prevent rheumatoid arthritis, decreases ectopic pregnancy and hospitalizations for pelvic inflammatory disease, and helps preserve bone mineral density to reduce risk of fractures. Large bodies of evidence from extensive research have clarified the perceived association of oral contraceptive use with cardiovascular disease and with breast cancer. Findings indicate that there is no increased risk of myocardial infarction or stroke associated with oral contraceptive use in healthy, nonsmoking, normotensive women. Although there is a 3- to 4-fold increased risk of venous thromboembolism with current oral contraceptive use, the absolute risk is very small and is half that associated with pregnancy. Women of all reproductive ages, including perimenopausal women, can realize many health benefits through oral contraceptive use, including improved health status later in life.