title: Procoagulant changes induced by oral contraceptives are balanced by an increased fibrinolytic tendency.
abstract: Oral contraceptives caused increased fibrinogen, FVII, FX, and fibrinolysis. The latter was associated with elevated FXII and PKK, while C1-INH was decreased, ATIII and alpha 2M were unchanged; it could not be accounted for by changes in t-PA, u-PA, PAI, plasminogen, alpha 2-AP, proteins C or S. HCII and alpha 1-PI were increased and may regulate the availability of thrombin and FXIa. The increased FXII/PKK dependent fibrinolytic potential and HCII may offset any increase in thrombin generation, while alpha 1-PI limits intrinsic coagulation.
authors.affiliation: Haematology Department, University College and Middlesex School of Medicine, London, U.K.
authors.forename: I J
authors.initials: IJ
authors.lastname: Mackie
authors.forename: S
authors.initials: S
authors.lastname: Campbell
authors.forename: M
authors.initials: M
authors.lastname: Gallimore
authors.forename: G
authors.initials: G
authors.lastname: Robinson
authors.forename: S J
authors.initials: SJ
authors.lastname: Machin
mesh_terms: D000328:Adult; D003276:Contraceptives, Oral; D005167:Factor VII / Q000378:metabolism; D005169:Factor VIII / Q000378:metabolism*; D005170:Factor X / Q000378:metabolism; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D005342:Fibrinolysis; D006801:Humans; D008597:Menstrual Cycle / Q000097:blood
chemical_list: D003276:Contraceptives, Oral; D005167:Factor VII; D005169:Factor VIII; D005170:Factor X; D005340:Fibrinogen