TF and hydrops fetalis: Serum transferrin levels (R2 = 0.170) measured in VLF (β = 0.089, p < 0.001), LF/HF ratio (β = 0.485, p = 0.001), LF (β = 0.081, p = 0.002), and HF (β = 0.171, p = 0.005) were significant predictors (Table 6).