The aim of the investigation was the analysis of TNFα gene expression in blood mononuclear cells and the production of cytokines (TNFα, IFN-α, TGF-β1) in the serum of patients with herpesvirus infection (HVI) and recurrent pregnancy loss (RPL) in their anamnesis, who underwent blood photomodification sensitized by photodithazine. There were examined and treated 74 patients with herpesvirus infection without recurrent pregnancy loss (group 1 — 36 women), and with recurrent pregnancy loss in their anamnesis (group 2 — 38 women). There was evaluated TNFα gene expression and the cytokine profile before the treatment, during and after the therapy. Patients in group 1 revealed a significant reduction of the dynamics of TNFα gene expression during the therapy, and in 60 % of the women there was marked the decrease of TNFα production. In group 2 the reliable reduction of the dynamics of TNFα gene expression and decreased production of TNFα in 10 days from the start of the treatment was detected in 62.5 % of patients. There was established a significant increase of the TGF-β1 level in patients of group 1 during the therapy. In group 2 there was revealed a mediated increase of TGF-β1 by the end of the treatment (the 18th–20th days), which is positive and contributes to the inhibition of the replication of herpes simplex virus. The results obtained indicate a positive effect of photosensitized modification of blood in patients with the relapsed HVI on the background of the RPL.