Levels of interferon-Γ and tumor necrosis factor-α in sera and cervical mucus of fertile and infertile women: implication in infertility

Concentrations of two immune cytokines, namely interferon-Γ (INF-Γ) and tumor necrosis factor-α (TNF-α), were determined in the sera and cervical mucus samples of fertile (n = 16), idiopathic infertile (n = 44), and immunoinfertile women (n = 45) to investigate their role, if any, in female infertility. Sera of idiopathic infertile women demonstrated significantly (P < 0.0001) higher levels of INF-Γ compared to those in fertile controls, whether expressed as pg/ml or pg/mg serum protein. Similarly, sera of immunoinfertile women demonstrated significantly (P = 0.0008) higher levels of INF-Γ compared to fertile controls and idiopathic infertile women. Cervival mucus of idiopathic infertile women also demonstrated significantly (P < 0.0001) higher concentrations of INF-Γ compared to those in fertile controls. Cervical mucus of immunoinfertile women demonstrated significantly (P < 0.0001) higher concentrations of INF-Γ compared to those in fertile controls and idiopathic infertile women. INF-Γ levels in serum did not significantly (P > 0.05) correlate (r = 0.12 - 0.43) with the concentrations in cervical mucus, when all the three groups were compared together. However, when the serum levels were compared with the cervical mucus concentrations by condition, only the idiopathic infertile group showed a significant (P = 0.005) correlation (r = 0.70). Serum levels of TNF-α did not differ significantly (P > 0.05) among three groups of women. Cervical mucus concentrations of TNF-α, however, varied among groups with levels being significantly (P = 0.04) higher-in idiopathic infertile women compared with fertile controls and in immunoinfertile women significantly (P = 0.0007) higher than in fertile controls as well as idiopathic infertile women. TNF-α levels in serum correlated (r = 0.65) significantly (P < 0.001) with the concentrations in cervical mucus when all the three groups were compared together or individually by infertility condition. These findings suggest the involvement of cytokines in infertility, and thus may have potential applications in diagnosis and treatment of female infertility.