Background The link between blood hypercoagulability, endothelial cell activation and infertility or in vitro fertilization (IVF) failure is a puzzling issue. Activation of platelets, endothelial cells and blood coagulation, proinflammatory and angiogenetic potential play important role in implantation and early embryonic development. Biomarkers of cellular hypercoagulability are associated with high risk of IVF failure. Soluble Leukemia Inhibitory Factor (LIF), an interleukin 6 class cytokine expressed in the trophectoderm of the developing embryo is an important regulator in the establishment of pregnancy. Endoglin (Eng), a co-receptor for TGF-β1 and TGF-β3 is implicated in vascular complications of pregnancy and particularly in preeclampsia.
Aim: The prospective longitudinal monocentric observational cohort study ROADMAP-IVF, evaluated the synergistic prognostic value of LIF and Eng with the biomarkers of cellular hypercoagulability in predicting the endometrial receptivity of fresh IVF cycles.
Materials and Methods. The ROADMAP-IVF enrolled 40 women eligible for IVF with normal blood count, PT, aPTT, Fg, renal and liver function. The control group (CG) consisted of 30 healthy women with history of uncomplicated pregnancies. Exclusion criteria: Use of anticoagulant or antiplatelet agents during the last 30 days before inclusion. Known cardiovascular disease, active cancer. Active corticosteroid treatment. Primary end-point: Echographically documented pregnancy at 7 weeks from implantation. Blood was collected on day 2 (D2) from the natural cycle and 6 days after hormone treatment initiation corresponding to D8 of the cycle. Procoagulant phospholipid-dependent clotting time (PPL-ct), tissue factor (TF), thrombomodulin (TM), von Willebrand factor (vWF) and D-Dimers (DDi) were measured with assays from Diagnostica Stago (Asnieres, France). P- and E-Selectin, LIF and Eng were measured with ELISA. Thrombin generation (TG) with the TF 5 pM PPP-Reagent ® was assessed on Calibrated Automated Thrombogram (Stago, France). The cut-off values for studied biomarkers have been selected on the basis of ROC analysis. Univariate and multivariate logistic regression analysis examined the associations between the biomarkers and the study outcome.
Results: 40 women were enrolled in the study. In 11 women pregnancy was confirmed with ultrasound and in 23 women no pregnancy was echographically documented. Age was not significantly different between the IVF (41 ys; range 22 - 48 ys) and the control group (40 ys; range 20 - 46 ys). At D2 and D8 the DDi and LIF were significantly higher in IVFG as compared to the CG. At D2 most of the patients had PPL-ct, DDi and MRI of TG higher than the upper normal limit (UNL). At D8 only TF was significantly increased as compared to the CG. Analytical data are presented in Table 1.
Age did not correlate with the levels of the studied biomarkers. Significant correlations (p<0.05) were found between DDi and ETP (r=0.35); TM, TF and P-Selectin (r=0.4) at D2; TF, LIF and Eng (r=0.5) at D2 and D8; P-Selectin and PPL-ct (r=-0.4) at D2; P-Selectin and TM (r=0.4), E-Selectin (r=0.5), LIF (0.4) at D2; E-Selectin and P-Selectin (r=0.5), TF (r=0.3), and LIF (r=0.4) at D2.
The ROC analysis showed that IVF failure was associate with DDi increase at D2 (AUC = 0.64); P-Selectin increase at D2(AUC = 0.57) and D8 (AUC = 0.61); TM increase at D8 (AUC = 0.61); TF increase at D8 (AUC = 0.57); LIF increase at D8 (AUC = 0.59); ETP increase at D2 (AUC = 0.67) and D8 (AUC = 0.67); Peak increase at D2 (AUC = 0.64) and D8 (AUC = 0.61). Prolongation of PPL-ct on D8 was predictive for positive pregnancy outcome(AUC 0.64).
Conclusion
The ROADMAP-IVF study showed that at least one out of four women eligible for IVF present biological evidence of activation of platelets, endothelial cells, blood coagulation or LIF upregulation. Hormone treatment administration does not significantly alter the proinflammatory or the hypercoagulable state. Among the studied biomarkers the levels of LIF, DDi, P-Selectine, TM and TF as well as the status of thrombin generation and PPL-ct showed a significant predictive value for the IVF outcome, particularly when measured at 6 days after hormone treatment administration. These findings will lead to the elaboration of an risk assessment model for IVF failure combining the selected biomarkers of hypercoagulability with LIF.
Disclosures
No relevant conflicts of interest to declare.
