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Abstract Background and objectives: Recurrent miscarriage (RM) is one of the most common reproductive disorders, generally considered to be the loss of three or more pregnancies before viability. One of the causes of this disorder is the immunological factors such as autoantibodies associated with anti-phospholipid syndrome. Material and Methods: this case-control study was conducted on 80 pregnant women divided into two equal groups of healthy and RM women in Gorgan. The subjects were asked to fill out a questionnaire and examined by a gynecologist to distinguish their condition, healthy or RM. The blood samples were kept at -20c and assessed by both ELISA 96 and automated ELISA processor with single dose ready-to-use test to measure β2GP1 autoantibodies of IgM and IgG. Results: the results indicate that % 7.5 of RM patients are seropositive for Anti-β2GP1 IgG, and % 5 for Anti-β2GP1 IgM , but in healthy pregnants , % 7.5 are seropositive for Anti-β2GP IgG , and %7.5 for Anti-β2GP1 IgM. Family history of abortion in RM group (33.5%) is significantly higher than healthy one (17.5%). Conclusion: based on the results, the difference between the level of Anti-β2GP1 IgM and Anti-β2GP IgG in case and control groups is not significant, but the production of this autoantibody is associated with pregnancy. Key words: Autoantibody, Antiphospholipid syndrome, Recurrent Miscarriage