ABSTRACT
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.
