 The efficacy of treatment with antithrombotic drugs during pregnancy in women with a history of RFL Intra Uterine Fetal Death IUFD and thrombophilia is still debated, due to scarcity of available data. Italian guidelines suggest the use of Low-Molecular-Weight Heparin LMWH in women with FV or FII mutations and previous otherwise unexplained obstetric complications, while guidelines released by RCOG suggest that heparin therapy during pregnancy may improve the live birth rate in women with second trimester loss associated with inherited thrombophilias. Hence, the idea to propose this prospective observational study comparing clinical data and outcomes in women with common inherited thrombophilias and in women without. 