title: The role of rotational thromboelastometry in assessment of haemostasis during pregnancy in women with factor XI deficiency.
abstract: BACKGROUND
  Women with factor XI (FXI) deficiency are at an increased risk of bleeding complications at delivery. Obstetric management is complicated by a lack of correlation between FXI level and bleeding risk.
  
  
  OBJECTIVE
  The aims of this study were to assess the difference in rotational thromboelastometry (ROTEM®) in parturient women with FXI deficiency compared to parturient and non-parturient controls and to evaluate the usefulness of ROTEM®in assessing bleeding risk at delivery in women with FXI deficiency.
  
  
  METHODS
  ROTEM®was performed on 60 women: 27 with FXI deficiency, 20 age-matched parturient controls and 12 non-parturient controls. Pregnancy outcomes and haemostatic cover was reviewed in 57 deliveries of women with FXI deficiency.
  
  
  RESULTS
  Women with FXI deficiency had a longer clotting time (CT) and clot formation time (CFT) (P < 0.001), reduced alpha angle (P < 0.001) but no difference in MCF (P = 0.054) compared to parturient controls. Compared to non-parturient controls, they had a longer CT (P < 0.001), but shorter CFT (P < 0.001), increased alpha angle (P < 0.001) and increased MCF (P = 0.005). ROTEM®was an additional helpful parameter in managing parturient women with FXI deficiency, reducing the need for factor administration.
  
  
  CONCLUSIONS
  ROTEM®demonstrated hypercoagulable changes during pregnancy in women with FXI deficiency. However, they took longer to clot compared to parturient controls, but had increased clot consolidation and clot strength compared to non-parturient controls. ROTEM®is an additional test that is helpful to assess bleeding risk and provision of appropriate haemostatic cover at delivery.
authors.affiliation: Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Department of Obstetrics and Gynaecology, Royal Free Hospital NHS Foundation Trust, Hampstead, London, UK.
authors.forename: J
authors.initials: J
authors.lastname: Davies
authors.affiliation: Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Department of Obstetrics and Gynaecology, Royal Free Hospital NHS Foundation Trust, Hampstead, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Harper
authors.affiliation: Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Department of Obstetrics and Gynaecology, Royal Free Hospital NHS Foundation Trust, Hampstead, London, UK.
authors.forename: R A
authors.initials: RA
authors.lastname: Kadir
keywords: blood products; factor XI; haemostasis; inherited coagulation disorders; pregnancy