Regulatory T Cells Show Dynamic Behavior During Late Pregnancy, Delivery, and the Postpartum Period.

Regulatory T cells (Tregs) are critical immunomodulators during early pregnancy by preventing maternal T-cell activation against fetal cells. However, how populations of maternal Tregs vary during and after pregnancy in humans is still unclear. Therefore, we investigated Treg subsets in the peripheral blood of pregnant women from late pregnancy through the postpartum period.

Impact of Labor on Peripheral Blood Maternal T-Cell Subsets and on Regulatory T and B Cells.

Purpose: Labor is thought to positively influence immune system development in the offspring, but studies investigating the impact of different modes of delivery on maternal immune system cells are scarce. Therefore, the aim of this study was to investigate the effect of labor on maternal peripheral blood T-cell subsets and on the recently described regulatory T and B cells.

Methods: Cross-sectional study comparing the absolute counts and percentages of peripheral blood T-cell subsets (maturation and activation profiles) and regulatory T and B cells between healthy pregnant women who delivered their newborns via elective cesarean (no labor; n = 14) and those who had a spontaneous vaginal delivery (after labor; n = 18).

Characterization of B cells in healthy pregnant women from late pregnancy to post-partum: a prospective observational study.

Background: B cells play a role in pregnancy due to their humoral and regulatory activities. To our knowledge, different maturational stages (from transitional to memory) of circulating B cell subsets have not yet been characterized (cell quantification and phenotype identification) in healthy pregnant women. Thus, the objective of our study was to characterize these subsets (as well as regulatory B cells) from late pregnancy to post-partum and to compare them with the circulating B cells of non-pregnant women.