title: Increased activation of blood coagulation in pregnant women with the Factor V Leiden mutation.
abstract: BACKGROUND
  The risk of venous thromboembolism is enhanced in pregnant carriers of the Factor V Leiden mutation. The primary aim of the study was to compare prothrombin fragments 1+2, soluble fibrin and D-dimer levels in pregnant Factor V Leiden mutation carriers with those in non-carriers. Secondary aims were to evaluate whether these biomarkers could predict placenta-mediated complications or venous thromboembolism, and to study blood coagulation after caesarean section with thromboprophylaxis and after vaginal delivery without thromboprophylaxis.
  
  
  METHODS
  Prothrombin fragments 1+2, soluble fibrin and D-dimer levels were studied longitudinally in 476 carriers with singleton pregnancies from gestational weeks 23-25 until 8-10 weeks postpartum.
  
  
  RESULTS
  Prothrombin fragments 1+2 and D-dimer levels gradually increased during pregnancy. D-dimer levels were higher in carriers, both during pregnancy and puerperium, compared to non-carriers. D-dimer levels above 0.5mg/l were found in about 30% and 20% of the heterozygous carriers at 4-5 and 8-10 weeks postpartum, respectively. Soluble fibrin levels were mainly unchanged during pregnancy, with no difference between carriers and non-carriers. Biomarker levels were similar in carriers with uncomplicated and complicated pregnancies.
  
  
  CONCLUSIONS
  Higher D-dimer levels indicate increased blood coagulation and fibrinolysis activity in carriers. The high proportion of carriers with D-dimer levels exceeding 0.5mg/l postpartum must be considered when assessing the probability of venous thromboembolism. Large overlaps in biomarker levels in normal and complicated pregnancies suggest that these biomarkers cannot be used as predictors. Thromboprophylaxis following caesarean section may prevent increased activation of blood coagulation.
authors.affiliation: Department of Obstetrics, Sahlgrenska University Hospital, Gothenburg, Sweden; Section for the Health of Women and Children, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden. Electronic address: ulla.kjellberg@hotmail.se.
authors.forename: Ulla
authors.initials: U
authors.lastname: Kjellberg
authors.affiliation: Department of Obstetrics and Gynaecology, Karolinska University Hospital, Stockholm, Sweden; Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Marianne
authors.initials: M
authors.lastname: van Rooijen
authors.affiliation: Department of Obstetrics and Gynaecology, Karolinska University Hospital, Stockholm, Sweden; Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Katarina
authors.initials: K
authors.lastname: Bremme
authors.affiliation: Department of Obstetrics, Sahlgrenska University Hospital, Gothenburg, Sweden; Section for the Health of Women and Children, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden; Department of Antenatal Care, Närhälsan Primary Care, Västra Götaland, Sweden.
authors.forename: Margareta
authors.initials: M
authors.lastname: Hellgren
mesh_terms: D000328:Adult; D001777:Blood Coagulation; D002585:Cesarean Section; D005165:Factor V / Q000235:genetics*; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006579:Heterozygote; D006801:Humans; D009154:Mutation; D010446:Peptide Fragments / Q000097:blood*; D049590:Postpartum Period; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000097:blood* / Q000235:genetics; D011498:Protein Precursors / Q000097:blood*; D011516:Prothrombin; D054556:Venous Thromboembolism / Q000097:blood* / Q000235:genetics; D055815:Young Adult
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; D010446:Peptide Fragments; D011498:Protein Precursors; C095381:factor V Leiden; C036309:fibrin fragment D; C029733:prothrombin fragment 1; C044183:prothrombin fragment 2; D005165:Factor V; D011516:Prothrombin
keywords: D-dimer; Factor V Leiden; Pregnancy; Prothrombin fragments 1+2; Soluble fibrin