Intrahepatic cholestasis of pregnancy in Chile: Analysis of epidemiological change and a microbiological hypothesis

Intrahepatic cholestasis of pregnancy is a gestational pathology with an unusual epidemiological and pathophysiological behavior that remains partially unexplained. Its current global incidence ranges from 0.1% to 2%. However, in Chile, the incidence reached up to 15% in the 1970s, with a marked decrease over subsequent decades, being nowadays about 1 to 2%. The reasons for this historical change are not fully understood. A literature-based analysis was conducted, focusing on clinical, microbiological, and epidemiological studies on intrahepatic cholestasis and other hepatobiliary diseases. The aim of this was to explore existing evidence and to propose a microbiological hypothesis that could help explain the epidemiological transition observed in Chile. Notably, the temporal reduction in incidence paralleled a nationwide decline in biliary disease and typhoid fever. We hypothesize that the eradication or significant reduction of certain pathogens, such as Typhi, may have contributed to the normalization of intrahepatic cholestasis of pregnancy rates in Chile.