PLOD1 and hydrops fetalis: Taken together, we postulate that the increased estradiol level is involved in Igf2-induced upregulation of the FSH receptor, rather than through downregulation of Igf2r, and the lower plasma LH level in HF-fed dams (i.e., the HF/C and HF/HF groups) may result from a negative feedback loop by inhibiting the production of gonadotropin in the hypothalamus because of high plasma E2 status.