LEP and hydrops fetalis: However, after 2, 4, and 8 weeks of dietary intervention, leptin levels were ~2.2-, 2.1-, and ~1.73-fold higher in HF rats (3.82, 7.69, and 11.52 ng/ml, respectively) than controls (1.74, 3.64, and 6.67 ng/ml, respectively) (Figure 3D).