New prognostic criterion for the outcome of pregnancy in patients with threatening preterm birth

Abstract

To identify new criteria for predicting the outcome of pregnancy in women with threatened preterm labor based on the establishment of the characteristics of differentiation and functional activity of memory T-cells in the population of CD8 + T-lymphocytes. The study involved 56 women with threatened preterm labor at 22-34 weeks of pregnancy. Depending on the outcome of pregnancy, patients were divided into 3 groups: Group I included 22 women by premature labor; group II - 34 women whose pregnancy ended by deliver at term. By tricolor flow cytofluorometry method the content of peripheral Tn, Tcm, Tem and Temra cells in CD8+ population was studied. Statistical analysis was carried out using programs «Statistica for Windows 13.0», «Microsoft Excel 2019» and «MedCalc 19.3». Patients with the threat of preterm birth were characterized by a significant increase in the relative content of CD8+ T-lymphocytes in the peripheral blood compared to the control group (p=0.001). When comparing this indicator in the subgroups of women with the threat of preterm birth, it was found that preterm birth was associated with significantly higher relative CD8 + lymphocyte counts (p=0.03) compared to the indicators of the subgroup of women who gave birth on time. When evaluating the results obtained, it was found that the percentage of CD8+Temra GranzymeB-producing cells in the group of patients with threatened preterm birth, whose pregnancy ended in preterm birth, was significantly lower than in the group of women who gave birth on time (p=0.003). The content of Tcm, Tem memory cells producing GranzymeB in the subgroups of women with pregnancy outcomes of timely and preterm birth did not have significant differences compared to the control group. Thus, the prediction of preterm birth is possible with a value of GranzymeB-producing CD8 + Tem equal to 8.2% or less (sensitivity-87.9%, specificity-85%, accuracy-87.9%). Thus, the identification of a new criterion will make it possible to predict preterm birth in a timely manner and promote the choice of optimal pregnancy management tactics, reasonable prevention of fetal respiratory distress syndrome and transfer of a woman to an obstetric hospital designed to provide high-tech care to premature newborns.