“…The number of patients with PE or eclampsia per study ranged from 14 to 300. Nine of the 11 studies used serum specimens to examine the IL-18 levels, [14][15][16]23,24,26,[28][29][30] and two studies were with plasma. 22,28 Eight of the 16 studies reported the use of plasma in the IFN-c assay, 17,19,20,31,36,37,40,42 while eight studies conducted in serum.…”