NR1H4 and gallstones: Women with ICP have an increased risk of developing gallstones.13 Given that women with ICP are hypercholesterolemic44 and that the type of gallstones associated with ICP are cholesterol-rich,45 it is conceivable that raised serum levels of sulfated progesterone metabolites enhance the formation of gallstones by disrupting cholesterol and bile acid metabolism pathways modulated by FXR.