Objective: To investigate fetal rats abnormal electrocardiograms in intrahepatic cholestasis of pregnancy(ICP).Methods: The animal model of intrahepatic cholestasis of pregnancy was induced by 17-α-Ethinylestradiol and Progesterone.The electrocardiograms of fetal rats by conceptual day 20th(Group1)

day 21st(Group2) were evaluated with Powerlab biologic signal extracting and analyzing system Chart 5 Software.Results: ①The serum total bile acids(TBA) levels of pregnant rats of ICP were 64.3±5.2(μmol/L) in group 1

78.5±4.5(μmol/L) in group 2

respectively

which showed significant differences(P<0.01).②It showed all normal electrocardiograms of fetal rats in Group1 over 90 minutes continuous observation.In Group2

fetal rats arrhythmias appeared after 29.3±6.4 minutes normal electrocardiograms observed initially;About 23.5±4.6(range 15-30)minutes fetal rats arrhythmias later

fatal ventricular arrhythmias came out and the fetal rats died suddenly.Conclusion: It demonstrated that fetal arrhythmias contribute to fetal sudden death in ICP.