PLOD1 and hydrops fetalis: Even though 5-min HRV time-domain and frequency-domain analysis parameters were not significantly changed following 7-day HS diet, similarly with the results from the stage 1 of the present study both LH and HF, as well as LF/HF tended to decrease following HS diet compared to LS, indicating a suppression of both, but more dominantly SNS than parasympathetic nervous system (PNS) activity following HS diet (Table 4).