In Italy, each year 500,000 couples refer to specialized centers due to reproductive problems. Among them, recurrent pregnancy loss (RPL) represents a problem of great importance, given that it affects up to 5% of women of childbearing age. Infertility, on the other hand, is a condition that currently covers 10-20% of couples of reproductive age, being idiopathic in 20% of cases. Accumulating evidence support the concept that changes of blood coagulation, generically defined as the presence of a thrombophilic state (congenital or acquired), are the basis of 40-70% of cases of multiple abortions or infertility. Several evidences support the hypothesis that endothelial dysfunction, a hallmark of a condition of low-grade inflammation, is one of the earliest manifestations of thrombotic phenomena. To date, it's believed that, while the antiinflammatory Th2 cytokines (i.e. interleukin-10) can exert a protective role in pregnancy, the pro-inflammatory Th1 ones (i.e. interferon-γ, tumor necrosis factor-α,) have deleterious effects on pregnancy outcome, including fertilization and implantation failure. Moreover, development of many pregnancy complications, first and foremost venous thromboembolism (VTE), recognizes similar mechanism(s). As VTE is the main preventable cause of mortality during pregnancy, thromboprophylaxis is mandatory according to individual VTE risk, influenced by the presence of thrombophilic conditions. In this review, we will analyze the relationship between thrombophilia and pregnancy complications, with particular focus on the role of inflammation. Subsequently, we will consider some issues related to the thromboembolic risk in pregnancy. Finally, the role of thromboprophylaxis in pregnancy will be discussed.