Keywords Animals, Female, Pregnancy, Bile Acids and Salts, Chromatography, Liquid, Fetus, Homeostasis, Liver, Progesterone, Receptors, Cytoplasmic and Nuclear, Signal Transduction, Sulfates, Swine, Tandem Mass Spectrometry, bile acid homeostasis, pregnancy, sulfated progesterone metabolites, FXR, sows Abstract Abnormally elevated circulating bile acids (BA) during pregnancy endanger fetal survival and offspring health; however, the pathology and underlying mechanisms are poorly understood.