IL6 and hydrops fetalis: Second, effective application of SF was confirmed by a 10-fold (p < 0.001; 2-way ANOVA) increase in circulating IL-6 in the mice subjected to this challenge [82.2 ± 27.0 pg/ml (C-SF) and 62.2 ± 36.3 pg/ml (HF+SF)], as compared with control sleep mice [9.1 ± 6.4 pg/ml (C) and 6.3 ± 2.8 pg/ml (HF)].