For many years, the term “foetal allograft” has been widely used for description of foetal immunological status during pregnancy. In such approach, immunological acceptance describing maternal reaction directed towards foetal antigen is understood as the state of recipient’s tolerance to an engrafted organ. Consequently, immunopathological recognition of foetal antigens that occurs in recurrent pregnancy loss or recurrent misscarriage and posibly pre-eclampsia should be viewed as graft-rejection like alloimmune reaction. However, there are still some doubts concerning this approach, as some proofs speak against it. For example, absence of expression of classical HLA antigens on the surface of trophoblast, foetal survival is not affected by the HLA-sharing between partners and no impact on the pregnancy outcome for the blocking-anti-HLA. Recurrent pregnancy loss is though to be due to increased activity of the innate immune system (especially natural killer cells) and organ specific auto-immunity as indicated by a higher prevalence of autoantibodies and its association with particular maternal class II HLA genotypes especially HLA-DR.