TNF and hydrops fetalis: Compared to human control serum, IL-6 and TNF-α concentrations were significantly higher in all HF sera (IL-6: control, 0.42 pg/ml (0.37-0.47 pg/ml) vs. HF, 6.83 pg/ml (4.26-14.04 pg/ml), p = 0.002; TNF-α: control, 0.68 pg/ml (0.63-0.74 pg/ml) vs. HF, 1.41 pg/ml (1.28-1.97 pg/ml), p = 0.002).