Detection of a procoagulable state during controlled ovarian hyperstimulation for in vitro fertilization with global assays of haemostasis.

INTRODUCTION: Controlled ovarian hyperstimulation during in vitro fertilization (IVF) causes profound increments in serum estradiol which may influence haemostasis and the ovarian hyperstimulation syndrome. In the present study we investigated the effect of the standard IVF-stimulation protocol on coagulation and fibrinolysis as assessed by different global haemostatic assays. MATERIALS AND METHODS: Blood samples were drawn from 31 women during the down-regulation phase when estradiol secretion is inhibited, and before egg retrieval, i.e. when estradiol levels are at supraphysiological levels, in the following called high level stimulation phase. Haemostasis was assessed during both treatment phases with 1) the calibrated automated thrombogram which measures thrombin generation, 2) overall haemostasis potential which measures fibrin formation and degradation and 3) fibrin gel permeability measurements which measures the quality of the fibrin network. RESULTS: Estradiol increased from <150pg/mL to 5889pg/mL (range 1620-19500pg/mL). We found both increased thrombin generation as measured by the calibrated automated thrombogram (p<0.001) and an increase in overall haemostasis potential (p<0.001) from time of down-regulation to high level stimulation. CONCLUSIONS: The assays used indicated procoagulable changes in haemostasis during in vitro fertilization. Further studies should evaluate their potential in the prediction of thrombosis and hyperstimulation.

Thrombin activatable fibrinolysis inhibitor and its relationship to fibrinolysis and inflammation during the acute and convalescent phase of ischemic stroke.

To investigate thrombin activatable fibrinolysis inhibitor (TAFI) in ischemic stroke and its relationship to fibrinolysis and inflammation, we investigated 32 patients with ischemic stroke during the acute phase and after 60 days. TAFI antigen levels, global markers of hemostasis (coagulation and fibrinolysis) and inflammatory markers were measured in plasma. TAFI antigen levels were significantly elevated at admission (128%; 109-151%) and at day 1 (129%; 109-152%) compared with day 60 (108%; 91-127%; both P < 0.01) and with healthy control individuals (99%; 76-122%; P < 0.05). In parallel, fibrinolysis assessed as the overall fibrinolysis potential (OFP), part of the overall hemostatic potential assay (OHP), was decreased at all time points compared with control individuals (P < 0.01 for all) and was found to be inversely related to TAFI (r = -0.40; P = 0.0008; n = 20). The OFP and the overall coagulation potential (another part of the OHP assay), and to a lesser degree TAFI, showed significant relationships to C-reactive protein and fibrinogen. In conclusion, elevated TAFI antigen levels may be a consequence of an acute phase reaction, and together with a depressed OFP suggest impaired fibrinolysis in patients with acute ischemic stroke. The OHP method may be useful as a complement to standard hemostatic variables in evaluating hemostasis in stroke patients.