A Study of the Predictive Value of Treg and Th1/Th2 Cytokines on Pregnancy Outcome in Patients with Recurrent Pregnancy Loss.

To investigate the influence of helper T cell type 1 (Th1)/Th2 cytokines and Treg cells on the pregnancy outcome of patients with recurrent pregnancy loss (RPL) and to reveal the predictive value of their combination on the pregnancy outcome.The 165 RPL patients admitted to the Reproductive Medicine Department of the Second Hospital of Lanzhou University from September 2019 to June 2021 served as the research subjects for the study. The subjects comprised a live birth group (102 patients) or a non-live birth group (63 patients) based on their pregnancy outcomes. All patients were tracked through the end of pregnancy. Flow cytometry was applied to determine Treg and Th1/Th2 cytokine levels in the peripheral blood of patients without pregnancy.The levels of interleukin-6 (IL-6), IL-2, IL-10, and Treg in the RPL live birth group were significantly higher than those in the non-live birth group. The ratio of TNF - α/ IL-6, NF-α/ IL-10, IFN- γ/ IL-6, IFN- γ/ IL-10 in the non-live birth group increased significantly. The area under the curve (AUC) of Th1/Th2 cytokines combined with Treg cells was 0.786 (95% CI: 0.712-0.860), the specificity was 76.2%, and the sensitivity was 74.5%.Treg and Th1/Th2 cytokines showed a predictive ability for the pregnancy outcome of patients with recurrent pregnancy loss and their higher combined predictive efficacy. Meanwhile, in the Th1/Th2 immune response, its ratio was more important than the expression of a single cytokine.