title: Quantitation of the thrombotic effects in artery and vein of the increase in coagulation factors during normal pregnancy in the rat.
abstract: Coagulation factors increase and fibrinolysin activity decreases in pregnant women. While the nett change in thrombotic tendency is unmeasured, venous thromboembolism increases five-fold in this group. We measured thrombus formation in vein and artery on standard platinum wires in 45 near-term pregnant rats, 19 pregnant for the first time and 26 for the second time, and in 33 never-pregnant controls. No significant increase in arterial thrombus occurred in the pregnant rats. Venous thrombus, however, increased by 65% in rats pregnant for the first time and 176% in those pregnant for the second time, compared to never-pregnant animals. Their mean increase in coagulation factors VIII, X, V, VII and II varied from 165 to 268%. Factor VIII level (r = 0.59, p < 0.05) correlated with venous thrombosis level, but the rarity of spontaneous thrombosis did not permit the limits of risk to be determined. Factors VII, X and V showed little correlation with thrombus weight (r = < 0.16) and Factor II an insignificant one. Monitoring factor VIII levels in pregnant women might help identify a group at risk of thromboembolism and establish a threshold for prophylactic intervention.
authors.affiliation: Department of Experimental Medicine, University College Galway, Ireland.
authors.forename: M M
authors.initials: MM
authors.lastname: Iomhair
authors.forename: S M
authors.initials: SM
authors.lastname: Lavelle
mesh_terms: D000818:Animals; D001158:Arteries / Q000473:pathology; D001779:Blood Coagulation Factors / Q000032:analysis*; D005260:Female; D005342:Fibrinolysis; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000097:blood* / Q000473:pathology; D011270:Pregnancy, Animal / Q000097:blood*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013927:Thrombosis; D014680:Veins / Q000473:pathology
chemical_list: D001779:Blood Coagulation Factors