Fibrin clot structure - pro-fibrinolytic effect of oral contraceptives in apparently healthy women.

Fibrin metabolism is influenced by many factors. The velocity of fibrin formation, genetic polymorphisms, fibrinolytic features and the structure of the fibrin clot are determinants of fibrin turnover. Oral contraceptives (OCs) have significant impact on the haemostatic system, by increasing the concentration of coagulation factors, plasminogen and tissue plasminogen activator activity, and decreasing the concentration of haemostatic inhibitors. The present study addresses the influence of OCs on fibrin structure and fibrin metabolism. The study included 70 women treated with seven different OC-formulations. Blood was collected at baseline and after six months of OCs. The plasma concentration of fibrinogen, thrombin-antithrombin complex (TAT), plasminogen, plasmin-antiplasmin complex (PAP), D-Dimer and thrombin generation measures were determined. Fibrin structure measures and fibrin clot lysis not affected by the plasma concentration of plasminogen activators and inhibitors were determined. OCs increased the concentration of fibrinogen, TAT, plasminogen, PAP and D-dimer significantly and affected measures of thrombin generation (p<0.001). The maximal optical density of fibrin (p<0.001), the fibrin fibre density (p=0.03), fibrin fibre diameter (p=0.003), fibrin mass-length ratio (p<0.001) and lysis per hour (p<0.001) increased significantly upon OC-treatment. Lysis per hour was not correlated to the concentration of plasminogen. We conclude that the effect of OCs on the coagulation system is balanced by alterations in fibrin structure, facilitating clot lysis and contributing to the fibrinolytic susceptibility already present in women treated with OC. These alterations may counterbalance the OC-induced increased thrombin generation and reduced coagulation inhibitory potential, contributing to maintenance of the haemostatic balance in women receiving OCs.

Bleeding patterns in peri and postmenopausal women taking a continuous combined regimen of estradiol with norethisterone acetate or a conventional sequential regimen of conjugated equine estrogens with medrogestone.

OBJECTIVES: The aim of this study was to compare the incidence of women presenting irregular bleeding episodes following 9 months of treatment with a low dose continuous combined hormone replacement therapy consisting of estradiol (E(2)) and norethisterone acetate (NETA) versus a sequential hormone replacement therapy consisting of conjugated equine estrogens (CEE) and medrogestone (MG). Secondary aims were to establish the relationship between menopausal age and the occurrence of irregular bleeding for both therapies and to assess the efficacy of both therapies in alleviating menopausal symptoms. METHODS: This was a stratified and randomised, open label study conducted with late peri and postmenopausal women at 35 sites in Austria and Germany. A total of 446 women were randomly allocated into two cohorts based on time since last bleeding and then stratified to either a low dose continuous combined therapy consisting of 1 mg E(2) and 0.5 mg NETA for 28 days or a sequential therapy consisting of 0.625 mg CEE for 28 days and 5 mg MG for the final 14 days. Bleeding and menopausal complaints were continuously assessed. Treatments were administered for 9 lunar months. RESULTS: The incidence rate of women presenting irregular bleeding episodes including spotting during cycle 9 was 12.2% with 1mgE(2)/0.5mgNETA and 25.8% with 0.625mgCEE/5mgMG (P = 0.0014). In the group of postmenopausal women (time since last bleeding > or = 12 months) the incidence of irregular bleeding during cycle 9 was 11.0% for 1mgE(2)/0.5mgNETA and 25.0% for 0.625mgCEE/5mgMG). In the group of late perimenopausal women (time since last bleeding 6-11 months) the incidence of irregular bleeding was similar for both treatments at cycle 3, but markedly less in patients with 1mgE(2)/0.5mgNETA at cycle 6 and 9, being significantly different compared to patients with 0.625mgCEE/5mgMG at cycle 6 (P < 0.05). The cumulative rate of amenorrhea (no bleeding or spotting) achieved with 1mgE(2)/0.5mgNETA was 89% for the postmenopausal women and 83.7% for the late perimenopausal women. Both treatments relieved menopausal complaints equally effective. CONCLUSIONS: Regarding the occurrence of irregular bleeding, the low dose continuous combined therapy was superior to the sequential therapy (0.625mgCEE/5mgMG). The low dose continuous combined E(2)/NETA regimen is also suitable for late perimenopausal women since more than 80% of the women had no bleeding or spotting after 9 months of treatment.

Plasma factor VII-activating protease is increased by oral contraceptives and induces factor VII activation in-vivo.

UNLABELLED: Oral contraceptive (OC) use influences the hemostatic system significantly and is a risk factor for development of cardiovascular disease. Factor VII-activating protease (FSAP) has potential effects on hemostasis. The 1601GA genotype of the 1601G/A polymorphism in the FSAP gene expresses a FSAP alloenzyme with reduced pro-fibrinolytic activity. Presently, we address whether OC use and OC formulation affect FSAP measures in human blood. Healthy women (n=588) were allocated to six cycles of OCs with estrogen contents of 20 µg (n=158), 30 µg (n=284), 35 µg (n=79) or 50 µg (n=67) combined with various progestins. FSAP genotypes, FSAP and factor VII (FVII) plasma measures were assessed at baseline and after 6 cycles of OC. The 1601GA genotype was present in 49 (8.3%) of the women and was associated with significantly reduced levels of FSAP (P≤0.001). OC use increased FSAP antigen by 25% and FSAP activity by 59% (P<0.001). The FSAP increase was comparable in the seven different OC treatment groups (P>0.05). The relative increase in FSAP activity was significantly higher in women carrying the 1601GG genotype (63%) than in women carrying 1601GA genotype (50%) (P=0.01) and was associated with an increased activation of FVII. IN CONCLUSION: OC use increases the plasma measures of FSAP. The increase in FSAP is comparable in the seven OC-groups studied but is more significant in women carrying the 1601GG genotype than in women with the 1601GA genotype and results in increased activation of FVII suggesting that FSAP-induced activation of FVII takes place in-vivo and not only in-vitro as hitherto described.

An open-label, comparative study of the effects of a dose-reduced oral contraceptive containing 0.02 mg ethinylestradiol/2 mg chlormadinone acetate on hemostatic parameters and lipid and carbohydrate metabolism variables.

OBJECTIVE: The study was conducted to compare the effects of 0.02 mg ethinylestradiol (EE)/2 mg chlormadinone acetate (CMA), given for 24 days each cycle, with those of 0.02 mg EE/0.15 mg desogestrel (DSG) and 0.03 mg EE/0.15 mg levonorgestrel (LNG), given for 21 days each cycle, on hemostatic, lipid, and carbohydrate metabolism parameters in healthy subjects, over six medication cycles. STUDY DESIGN: A randomized, multicentre, open-label, Phase II trial measured markers of hemostasis, and of lipid and carbohydrate metabolism in 165 subjects randomly assigned to treatment with one of three combined oral contraceptives (COCs). RESULTS: EE/CMA and EE/DSG had a similar effect on hemostatic parameters, the EE/LNG group showed comparatively smaller increases in the activity of factor VII [8.1% vs. 36.6% (EE/CMA) and 28.2% (EE/DSG)], protein C [5.9% vs. 32.9% (EE/CMA) and 21% (EE/DSG)] and endogenous thrombin potential-based activated protein C resistance [44.1% vs. 93.5% (EE/CMA) and 108.1% (EE/DSG)], and in contrast, free protein S levels decreased in the EE/CMA and EE/DSG groups (-12.7% and -4.3%, respectively) but rose in the EE/LNG group (20.4%). In all treatments, total cholesterol, total triglyceride and apolipoproteins increased. Levels of very low-density lipoprotein cholesterol particularly rose across all groups. Slight increases in high-density lipoprotein (HDL) cholesterol were observed for EE/CMA (14.6%) and EE/DSG (8.5%), with a rise above the upper limit of normal in 30% of the subjects taking EE/CMA. Conversely, for EE/LNG slight decreases in HDL cholesterol were observed (-12.4%) lipoprotein (a) levels decreased in the EE/CMA (-6.6%) and EE/LNG (-16.9%) groups and were unchanged in the EE/DSG group. CONCLUSIONS: The changes observed were typical of those seen across low-dose COCs that differ according to commonly-used progestogens.

The effects of two monophasic oral contraceptives containing 30 mcg of ethinyl estradiol and either 2 mg of chlormadinone acetate or 0.15 mg of desogestrel on lipid, hormone and metabolic parameters.

BACKGROUND: This study was conducted to compare the effects of two monophasic oral contraceptives (OCs) containing ethinyl estradiol (EE) 30 mcg+either chlormadinone acetate (CMA) 2 mg (Belara) or 0.15 mg desogestrel (Marvelon) on lipid, hormone and other relevant metabolic parameters. STUDY DESIGN: Markers of lipid and carbohydrate metabolism, and reproductive hormone levels, were measured in 45 subjects randomly assigned to 6 months of treatment with one of the two OCs. The cortisol response to adrenocorticotrophic hormone (ACTH) stimulation was also evaluated. RESULTS: In both treatment groups, triglycerides, high-density lipoprotein cholesterol (HDL-C), apolipoprotein (Apo) AI and Apo AII levels increased; low-density lipoprotein cholesterol (LDL-C) and the LDL-C/HDL-C ratio decreased; and total cholesterol and lipoprotein(a) were unchanged during treatment. Effects on HDL-C, Apo AI, LDL-C and the LDL-C/HDL-C ratio were more evident in the EE 30 mcg+CMA 2 mg group. Follicle-stimulating hormone, luteinizing hormone and androgen levels decreased and sex hormone-binding globulin levels increased in both groups. Both OCs increased basal cortisol levels and cortisol response to ACTH. Oral contraceptive did not have a clinically significant impact on carbohydrate metabolism. CONCLUSIONS: Both low-dose monophasic OCs had comparable effects on lipid, hormone and metabolic parameters during six cycles of treatment in healthy female subjects. There was some evidence of a beneficial effect on atherogenic cardiovascular risk markers, which was slightly more pronounced with EE 30 mcg+CMA 2 mg.