Inflammatory changes in maternal peripheral blood leucocytes in the second trimester of pregnancy

Our previous work has shown a maternal systemic inflammatory response (MSIR) to be present in the third trimester of normal pregnancy. Our aim in this study was to investigate whether there is any evidence for this inflammatory response at an earlier gestational age, namely the second trimester. Twelve pregnant women who attended our high-risk antenatal clinic, and whose pregnancies were progressing normally, were studied at 24 weeks’ (±7 days) gestation, following uterine artery Doppler measurement. Six had resistance index ratios ≥ 0.6 bilaterally, which is used as a predictor of future development of pre-eclampsia, and six had at least one value <0.6. Whole blood flow cytometry was performed on a peripheral blood sample from each woman. Evidence of leucocyte activation was sought by measuring the expression of a variety of cell surface markers (including CD11b, CD49d, and CD64), and the production of intracellular reactive oxygen species (iROS). The results were compared with a group of non-pregnant co...