Ovarian Hyperstimulation and Fibrin Clot Properties.

Inclusion Criteria: * infertility defined based on the WHO 2010 criteria Exclusion Criteria: * ovarian involvement * oral contraceptives use within previous 3 months * dienogest therapy within 3 months until ART * thrombotic events in the medical history * severe hypertension * diabetes mellitus * the presence of known VTE risk factors, including obesity, recent major surgery with prolonged immobilization or trauma, * deficiency of antithrombin, protein C or protein S, * antiphospholipid syndrome, * known malignancy, * any chronic inflammatory diseases (e.g. rheumatoid arthritis) * advanced chronic renal disease (estimated glomerular filtration rate \[eGFR\] \<30 ml/min), * international normalized ratio (INR) more than 1.2 at the day of blood draw * pregnancy.