Comparative analysis of transcriptional activity of human nucleolus organizer regions (NOR) of the chromosomes in the group of the control phenotypically healthy individuals (I) and in the spouses with repeated spontaneous abortions (II) was conducted in an attempt to verify the hypothesis: whether elimination of zygotes having received a very large or very small number of the copies of active rRNA genes may serve as a factor decreasing the fecundity of some spouses? It has been shown that the groups I and II have no differences in total activity of 10 NOR (Ag staining, rating estimation). At the same time, the II group is characterized by higher, in comparison with the I, heterogeneity of Ag-NOR variants in homologues of 5 nucleolus-organizing chromosomes. As a result, in the individuals of the group II the gametes are formed which are more heterogenous than in the group I for the Ag-NOR pattern variants. The imitation computer experiments revealed that in the group II elimination of zygotes as a consequence of inherited Ag-NOR variants combination should occur more frequently (in 22.2% cases) than in the group I (15.9%), p < 0.05. Thus, the hypothesis under test was substantiated in the present study.