title: Changes in thrombin generation and D-dimer concentrations in women injecting enoxaparin during pregnancy and the puerperium.
abstract: BACKGROUND
  It is well accepted that the gravid state is hypercoagulable and a significant cause of both maternal morbidity and mortality in the Western world. Although thrombin generation is reported to be increased in pregnant women, uncertainty exists on the pattern of thrombin generation change during this time. The aim of this study is to describe thrombin generation changes and D-dimer concentrations in women injecting enoxaparin during pregnancy the postnatal period.
  
  
  METHODS
  One hundred and twenty-three women injecting enoxaparin had their thrombin generation, as measured by Calibrated Automated Thombinography (CAT), repeatedly assayed during pregnancy, once in each trimester, at delivery and 8 weeks post-partum. Furthermore, to understand the impact enoxaparin has on D-dimer concentrations during pregnancy, D-dimer concentrations were measured monthly in the recruited women.
  
  
  RESULTS
  Thrombin generation was found to increase in the first trimester (mean endogenous thrombin potential (ETP): 1391 nmol/L.min), further increasing during the second trimester (mean ETP: 1757 nmol/L.min), after which it plateaued through to delivery, where it peaked (mean ETP: 1857 nmol/L.min) and then fell back at 8 weeks post-partum (ETP: 1293 nmol/L.min). In contrast D-dimer concentrations increased exponentially during the antenatal period, despite the enoxaparin prescription.
  
  
  CONCLUSIONS
  Our results provide further evidence on alterations of thrombin generation during pregnancy and the postnatal period.
authors.affiliation: Department of Haematological Medicine, King's Thrombosis Centre, King's College Hospital NHS Foundation Trust, Denmark Hill, London, SE5 9RS, UK. jig.patel@kcl.ac.uk.|Institute of Pharmaceutical Science, King's College London, London, UK. jig.patel@kcl.ac.uk.
authors.forename: Jignesh P
authors.initials: JP
authors.lastname: Patel
authors.affiliation: Department of Haematological Medicine, King's Thrombosis Centre, King's College Hospital NHS Foundation Trust, Denmark Hill, London, SE5 9RS, UK. rajpatel@nhs.net.
authors.forename: Raj K
authors.initials: RK
authors.lastname: Patel
authors.affiliation: Department of Haematological Medicine, King's Thrombosis Centre, King's College Hospital NHS Foundation Trust, Denmark Hill, London, SE5 9RS, UK. lara.roberts@nhs.net.
authors.forename: Lara N
authors.initials: LN
authors.lastname: Roberts
authors.affiliation: Department of Obstetrics and Gynaecology, King's College Hospital NHS Foundation Trust, London, UK. michael.s.marsh@kcl.ac.uk.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Marsh
authors.affiliation: Model Answers Pty Ltd, Brisbane, Australia. bruce@model-a.com.au.
authors.forename: Bruce
authors.initials: B
authors.lastname: Green
authors.affiliation: Institute of Pharmaceutical Science, King's College London, London, UK. graham.davies@kcl.ac.uk.
authors.forename: J Graham
authors.initials: JG
authors.lastname: Davies
authors.affiliation: Department of Haematological Medicine, King's Thrombosis Centre, King's College Hospital NHS Foundation Trust, Denmark Hill, London, SE5 9RS, UK. roopen.arya@nhs.net.
authors.forename: Roopen
authors.initials: R
authors.lastname: Arya
mesh_terms: D000293:Adolescent; D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage*; D044383:Black People; D017691:Caribbean Region / Q000208:ethnology; D017984:Enoxaparin / Q000008:administration & dosage*; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D049590:Postpartum Period; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000188:drug therapy / Q000517:prevention & control*; D011261:Pregnancy Trimester, First / Q000097:blood; D011262:Pregnancy Trimester, Second / Q000097:blood; D011263:Pregnancy Trimester, Third / Q000097:blood; D011295:Prenatal Care; D013917:Thrombin / Q000096:biosynthesis*; D054556:Venous Thromboembolism / Q000188:drug therapy / Q000517:prevention & control*; D044465:White People; D055815:Young Adult
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin; D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D; D013917:Thrombin