Recurrent spontaneous abortion of unidentified cause or idiopatic is an important problem of reproduction health. In this study, the study has been started of one of the mechanisms that could act in the pathology of human pregnancy. The general hypothesis proposed, is that in the case of patients with recurrent spontaneous abortion of non identified cause (RSA) there are phenomenons in the materno/fetal/placentary means that manifest themselves in harm to the functionality and/or vitality of placentary tissue. The hypothesis was consistent with the finding of massive activation of cellular death in all the cases with RSA studied in this work.