BACKGROUND Although an association between
thrombophilia and pregnancy loss has been observed in many studies, little is known about the pathophysiological mechanisms behind this association. Considering the association between
thrombophilia and pregnancy loss, the efficacy of antithrombotic
therapy for women with pregnancy loss (with or without
thrombophilia) has been studied for the past 30 years. METHODS We performed a comprehensive review of the literature on the strength of the association between
thrombophilia and pregnancy loss, the pathophysiological mechanisms and the efficacy of antithrombotic
therapy to increase the chance of live birth. RESULTS The association between pregnancy loss and
thrombophilia varies according to the type of
thrombophilia (e.g.
antiphospholipid syndrome versus forms of inherited
thrombophilia) and according to the type of pregnancy loss (single versus recurrent pregnancy loss and early versus late pregnancy loss).
Thrombophilia may induce
thrombosis in decidual vessels or impair placentation through
hypercoagulability and
inflammation, but these hypotheses need further verification. For women with
antiphospholipid syndrome, evidence from small-sized trials suggests a beneficial effect of antithrombotic
therapy but additional randomized controlled trials are essential to confirm this. Whether antithrombotic
therapy increases the chance of live birth in women with inherited
thrombophilia is unknown. Recent randomized controlled trials have consistently shown that antithrombotic
therapy does not increase the chance of live birth in women with unexplained
recurrent miscarriage. CONCLUSIONS There are large gaps in knowledge and a lack of evidence for treatment of women with pregnancy loss with
thrombophilia. To provide a solid base for clinical practice, further studies on the role of coagulation in reproduction, as well as international collaborations in randomized controlled trials of antithrombotic
therapy in women with pregnancy loss, and
antiphospholipid syndrome or inherited
thrombophilia are urgently needed.