The analysis of hemastasiological researches on hidden acquired and genetic forms of thrombophilia in women with burdened anamnesis of the syndrome of fetus loss (SFL), preeclampsia. It is established that acquired thrombophilia conditioned by the APS in patients with SFL is 28.6 % cases. The mutation МTHFR C677T — (45.2 %) appeared the most widespread. The factor of APS action potentioning is genetic thromphilia: APS and MTHFR C677T in SPP — 17.4 %, in preeсlampsia — 33.3 %, APS and FV Leiden at SFL — 9.6 %, in preeсlampsya — 7.2 %. Pathogenetically grounded prevention of thromboembolism in these obstetric complications with low-molecular heparin сleхanе, initiated with the fertile cycle and at the stage of trophoblast invasion, in the absolute majority of cases (92–96 %) considerably improves the outcome of pregnancy.
