Maternal immunophenotypic profile in normal pregnancy and preterm birth

UNLABELLED: During normal pregnancy, the maternal immune response achieves a split tolerance state towards the fetal allograft, expressed by immunophenotypic profile. This may be impaired in the preterm birth. Our study aimed to analyze the immunophenotypic profiles of the peripheral and retroplacental blood in women with normal pregnancy and preterm birth. Blood leukocyte populations were assessed by flowcytometry in nine normal at term pregnancies, five preterm births and eight nonpregnant controls. Our results showed in normal pregnant women as compared to controls, a significant decreased number of lymphocytes, monocytes and B cells, while granulocytes, T-lymphocytes and the T CD8+ subsets were elevated. The CD4/CD8 ratio was significantly decreased, especially in the retroplacental blood. The preterm birth group demonstrated a significantly elevated number of lymphocytes and B cells, lower T CD8+ cells and an increased CD4/CD8 ratio, in comparison with normal pregnancies group. CONCLUSION: Normal pregnancy determines a suppressive immunophenotypic profile that is impaired in the preterm birth suggesting its immunological involvement.