Impact Of Thrombin Generation, Tissue Factor Activity and Thrombomodulin Activity On The Positivity Of Assisted Reproductive Technique In Infertile Women

Women undergoing assisted reproductive techniques (ART) are given gonadotrophins to promote the development of multiple follicles within their ovaries. This treatment may be associated with a risk of ovarian hyperstimulation syndrome and venous or arterial thrombosis. The association of clinical and biological criteria of hypercoagulability might contribute to the identification of patients at risk and probably could predict success of ART.

The aim of this study was to evaluate thrombin generation, thrombomodulin activity, tissue factor (TF) activity, and procoagulant phospholipids in selected women undergoing ART. We also assessed the potential correlation between the levels of the studied biomarkers and the outcome of the ART.

A cohort of 27 infertile women eligible for ART and 30 healthy age matched women was studied. All patients were Caucasian aged 33.75 ± 3.52 years and weight 61.08 ± 8.10 kg. Women included in the study did not present any personal or family history of VTE or known thrombophilia. They did not present any signs of hemorrhagic syndrome and did not suffer from any known autoimmune disease. Blood samples were taken under fasting conditions at the following time-points: at the inclusion (T0), between the 5th and 8th day of ovarian stimulation with gonadotrophines (T1) and at the day of HCG administration (T2). Thrombin generation (TG) in plasma was assessed using the Calibrated Automated Thrombogram assay (using, PPP-Reagent-5pM TF from Diagnostica Stago, France), Plasma levels of thrombomodulin activity (TMa), and TF activity (TFa) were measured by home-made tests, Procoagulant phospholipids (PPL) dependent clotting time was measured using a factor Xa-based assay (STA-R Procoag-PPL, Diagnostica Stago, France).

The endogenous thrombin potential (ETP), PPL, TMa and TFa were significantly higher in the ART-T0 group as compared to the control group. At ART-T2 a significant increase of TG was observed as compared to ART-T0.

At ART-T0 44.5%, 44.4 % and 33.3 % of women had ETP, TFa and TMa higher than the Upper Normal Limit respectively (UNL = mean+2 S.D.). Among with negative ART 89% and 91.7% showed TMa and TFa levels > UNL at ART-T0. At T1 50% of women had a least one parameter of TG higher than the UNL. At ART T2 65.2 % of women had TG > UNL. At the same time, 87.5% and 83.4% of women with negative ART had levels of TMa and TFa > UNL.

This study analyzed the profile of thrombin generation in infertile women eligible for ART and investigated the influence of hormone treatment with gonadotropins and HCG on TG and levels of TMa and TFa. Hypercoagulability, in terms of increased ETP is present in 46% of infertile women eligible for ART. These women remain in a hypercoagulable state throughout the entire period of hormone treatment. The most significant finding of this study was that 33% of patients show a value superior to the UNL for thrombomodulin and 45% for tissue factor. Interestingly 89%of women with negative ART had TMa higher than the UNL. Respectively 91% of women with negative ART had TFa levels higher than the UNL

No relevant conflicts of interest to declare.