We also suggested that some potential immune traits, such as IFN-γ and IL-4 levels, as well as the CD4+/CD8+ ratio and could be correlated with protection against abortion (higher IL-4 levels and CD4+/CD8+ ratio) or with poor prognosis or inflammatory conditions (higher IFN-γ production and increase of CD8+ lymphocytes). This evidence concerns the gene IFNG and abortion.