Effects of two low-dose oral contraceptives on circulating components of the coagulation and fibrinolytic systems.
We studied the effects on plasma levels of coagulation and fibrinolysis factors of two currently used "sub-50" oral contraceptive preparations (OCs), one containing 750 micrograms lynestrenol and 37.5 micrograms ethinyl estradiol (LYN-EE) and the other containing 150 micrograms levonorgestrel and 30 micrograms ethinyl estradiol (LNG-EE), in groups of about 25 women aged 21 +/- 2 years. After 3 months, plasminogen levels increased in the two experimental groups (LYN-EE and LNG-EE), by 40% and 32%, respectively. This change was positively correlated with changes in ceruloplasmin levels, indicating that an estrogenic effect might be involved. Histidine-rich glycoprotein concentration decreased by 26% and 16%, respectively. Tissue-type plasminogen activator (t-PA) activity increased by 260% and 167%; t-PA antigen decreased by 12% and 18%, and t-PA inhibitor activity decreased by 31% and 32%, respectively. In the coagulation system, in both groups factor XII increased by 47% and 34%, respectively. The main inhibitor of factor XII, C1-inactivator, decreased slightly, but this was significant only in the LNG-EE group. The von Willebrand factor antigen fell by 8% and 9%, whereas factor VIII activity did not change. Antithrombin III antigen decreased by 14% in both groups. Factor IX activity increased by 15% and 21%. The difference in hormonal effects of both preparations was reflected by the increases in sex hormone binding globulin (by 130% and 21%) and ceruloplasmin (by 98% and 51%), indicating that LYN-EE had a more estrogenic potency than LNG-EE. In a control group of 25 matched subjects, who were observed simultaneously, we found no significant changes.(ABSTRACT TRUNCATED AT 250 WORDS)
D000328:Adult; D001777:Blood Coagulation / Q000187:drug effects*; D001798:Blood Proteins; D003277:Contraceptives, Oral, Combined / Q000008:administration & dosage / Q000009:adverse effects*; D004997:Ethinyl Estradiol / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D005342:Fibrinolysis / Q000187:drug effects*; D006801:Humans; D016912:Levonorgestrel; D008234:Lynestrenol / Q000008:administration & dosage / Q000009:adverse effects; D009644:Norgestrel / Q000008:administration & dosage / Q000009:adverse effects; D010958:Plasminogen / Q000032:analysis; D011506:Proteins; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D010959:Tissue Plasminogen Activator / Q000097:blood; D014841:von Willebrand Factor / Q000032:analysis; D000099053:Histidine-Rich Glycoprotein
D001798:Blood Proteins; D003277:Contraceptives, Oral, Combined; D011506:Proteins; D012738:Sex Hormone-Binding Globulin; D000099053:Histidine-Rich Glycoprotein; D014841:von Willebrand Factor; D009644:Norgestrel; D004997:Ethinyl Estradiol; D016912:Levonorgestrel; D010958:Plasminogen; D010959:Tissue Plasminogen Activator; D008234:Lynestrenol