Distribution of mononuclear cells during pregnancy.

Leucocyte and lymphocyte counts, the distribution of erythrocyte rosette-forming cells (E-RFC), erythrocyte-antibody-complement rosette-forming cells (EAC-RFC), cells bearing surface membrane immunoglobulin (SMIg), latex-ingesting cells and the PHA stimulation index of lymphocytes were evaluated in both pregnant and non-pregnant women. In the gravid female leucocytosis due to neutrophilia is seen, and the PHA-induced transformation of maternal lymphocytes in the absence of autologous plasma remains unaltered. There was a rise in the percentage of EAC-RFC and cells bearing SMIg during a pregnancy, but after monocyte adsorption on plastic dishes of the mononuclear cells, obtained after Ficoll-Hypapue centrifugation, this increase is abolished. There is a significant increase of the number of latex-ingesting cells during pregnancy. These findings indicate a significant increase of the monocytes during pregnancy.