Treatment modalities stratified by underlying etiologies of RPL may improve pregnancy outcome. Administration of IVIG is likely to have clinical efficacy in RPL women with cellular immune abnormality.

Reproductive failure (RF) is the inability to conceive or to carry a pregnancy to term, and its prevalence is not negligible. Pregnancy is a prothrombotic condition, which can be abnormally exaggerated in women with thrombophilia. Antiphospholipid syndrome is a cause of RF and effectively managed with heparin and aspirin. However, there are yet insufficient data in patients with RF and inherited thrombophilia. This review focuses on the significance of inherited thrombophilia and RF and the role of anticoagulants in pregnancy outcomes. A few randomized case‐control studies have investigated the effect of anticoagulation in RF with thrombophilia, and the results are yet debatable. Some inherited thrombophilia including mutations of factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase and protein S deficiency are associated with RF and/or late pregnancy complications. There are several implications which influence the diagnosis and treatment. First, there is a lack of studies revealing appropriate thrombophilia markers and its cutoff values for RF specifically. Second, some thrombophilia markers change with sex and age. Lastly, the study designs of previous studies are heterogeneous in selecting the thrombophilia markers and drugs. Further studies to find adequate thrombophilia markers of RF are warranted and eventually elucidate the subgroups beneficial to anticoagulation treatment.

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Calcitriol facilitated EMT induction and expression of MMPs via ERK signaling pathway, which promoted the invasive capability of EVTs. Further studies are warranted to elucidate the potential application of vitamin D in the prevention of pregnancy complications.

Decidual stromal cells (DSCs) are known to regulate trophoblast invasion via unveiled mechanism yet. And nucleotide-binding oligomerization domain-containing protein 1 (NOD1) may influence on this DSC-trophoblast interaction. We investigated the mechanism underlying the DSC-mediated regulation of trophoblast invasion and the effect of NOD1 on their cross talk. Using human primary DSCs, BeWo cell invasion was measured. Cytokine secretion and MAP kinase signaling were examined in DSCs following treatment with NOD1 agonist, Tri-DAP. DSCs secreted IL-8 and increased trophoblast invasion. Tri-DAP further increased IL-8 secretion from DSCs via JNK pathway and facilitated both MMP-2 production and trophoblast invasion compared with control. Upon cotreatment of IL-8 and anti-IL-8 antibody to BeWo cells, the number of invading trophoblasts and MMP-2 production decreased significantly. These results suggest that IL-8 from DSCs may play a role to increase the invasiveness of trophoblast cells into the decidua via NOD1/JNK pathway.