Functional aspects of T-lymphocyte subsets in pregnancy.

Several recent reports have suggested that a decrease in circulating T helper cells may contribute to the relative immunodeficiency of pregnancy. To investigate the significance of these findings, 90 pregnant women were evaluated. The results of this study indicate that although pregnant women have a decreased proportion of T helper cells, they do have adequate T helper cell function as determined by an in vitro immunoglobulin synthesis assay and a T-lymphocyte colony-forming assay. Based on these studies it is unlikely that decreased numbers of T helper cells are primarily responsible for the immunodeficiency of pregnancy.