 Recurrent pregnancy loss is defined as two or more consecutive pregnancy loss before 20 weekse of gestation 1. It affects about 1-5 of women of reproductive age. This not only causes significant physical and mental problems in families, but also a heavy economic burden on families and health systems 2, 3 Recurrent pregnancy loss RPL is a syndrome caused by multiple etiologies such as anatomical, endocrine, genetic, infectious, immunological, thrombotic and unexplained etiologies hence an investigation of underlying etiologies is often complicated When the conventional investigation scheme is applied, up to 60 of women with RPL remain unexplained 4. Recent studies have indicated that immune inflammatory and thrombotic conditions are two major under-lying pathologies for RPL 5. Approximately 20 of women with RPL have autoimmune conditions, such as antiphospholipid antibody APA6,antinuclear antibody ANA, anti-thyroperoxidase antibody and anti-thyroglobulin antibody7,8. 