The aim: To study placenta annexin V receptors, and serum antibodies against ph-acid, ph-ethanolamine, ph-glycerol, ph-inositol, ph-serine, cardiolipin, β2-glycoprotein I, prothrombin a annexin V in patients with recurrent pregnancy loss. Setting: Department of Gynecology and Obstetrics and Faculty Hospital of Charles University, Plzen. Methods: We examined sera and placenta tissue from 156 patients in reproductive age with unexplained repeated pregnancy loss. Control group of eighty-four fertile healthy women was included. ELISA methods were used for detecting a panel of sera of anti-phospholipid antibodies (aPLs). Immunolocalization of annexin V receptors in 143 trophoblast-placenta specimen of 156 patients was investigated by the immunofluorescence technique using Annexin V-FITC, Apoptosis and Annexin V-CY3 commercial kits. Results: Positivity for anti-phospholipid antibodies mainly against ph-serine, ph-inositol, and ph-ethanolamine was found together in 80.8%, anti-prothrombin antibodies in 12%, and anti-annexin V antibodies in 13.5% women. No significant levels of aPLs were found in 6 controls. Immunohistopathology of placenta also exhibited some changes manifested by the presence of apoptotic and necrotic cells in trophoblast, and very few microtrombotization in some intervillous spaces and in placenta vessels. Conclusion: Our detailed study demonstrated the prevalence of majority of antiphospholipid antibodies as one of the high risk factor of repeated reproductive failure. Very low microthrombosis in placenta could be explained by the changes of haemocoagulation properties out of uterus.

        Key words: placenta, annexin V, pregnancy loss, phospholipids