Pathogenetic substantiation of preterm births prevention methods

Abstract

The study of the pathogenesis of premature birth is one of the important issues of modern obstetrics. This could contribute developing a scientifically sound program for predicting and preventing this complication of pregnancy. The aim of the study was to investigate the blood variables of the immune system and connective tissue metabolism in women with preterm birth at 23-36 weeks of gestation. Materials and methods. A total of 227 pregnant women were examined, 190 of whom had clinical signs of threatened preterm birth. Group I included 48 women with a threatened preterm delivery resulted in childbirth between 23 and 27 weeks. In group II, 142 women at risk of preterm birth were observed from 28 to 36 weeks. Group III included 37 women with a healthy pregnancy, completed at 38-41 weeks. Result. The number of lymphocytes and their subpopulations, the content of connective tissue metabolites in the blood of the examined patients were studied. In women of group, I relatively to women of group III there was an evident (p < 0.001) decrease in blood level of CD3 + -marker of T-lymphocytes by an average of 23 %, which suggests the presence of immunodeficiency and considered as a stress response. In women with preterm birth at 28-36 weeks of gestation (group II), the relative level of CD3 + in the blood, on the contrary, slightly but probably (p = 0.014) increased compared to women with healthy pregnancy by an average of 13%. A significant decrease in the immunoregulatory index in women of group I is associated with the suppression of the T-helper component and emphasizes the presence of T-cell immunosuppression. The decrease in the index in women of group II occurred due to cytotoxic T-lymphocytes. Сonclusions. Thus, the work confirms the opinion of R. Romero on the role of immune "rejection" in the third trimester, associated with the HLA-incompatibility of mother and fetus. In women of group I, compared with women of group III, there was a more pronounced increase in serum free oxyproline - a marker of collagen breakdown than bound oxyproline - a marker of collagen synthesis. Group II women also had a simultaneous increase in the level of the two oxyproline fractions, but more pronounced for the protein-bound fraction. This suggests that the violation of the metabolism of connective tissue leads to the destruction of the collagen matrix of the cervix and its shortening. Studies suggest that cerclage or insertion of pessary should be used to prevent cervical incompetence in the second trimester due to metabolic disorders in the connective tissue. The use of progesterone is appropriate for prevention of "short cervix" syndrome, as well as the possible immunosuppressive effect of the latter. The established signs of autoimmune processes require screening for antiphospholipid syndrome and the appointment, if confirmed, of anticoagulants.