Intrahepatic cholestasis of pregnancy: review of the literature

Abstract

Introduction. Intrahepatic cholestasis of pregnancy (ICP) is a liver disease, which complicates 0.5-1% of all pregnancies, associated with raised serum levels of bile acids and increased rates of adverse fetal outcomes. ICP is described as pruritus in pregnancy as a main symptom. Aim of the study. To highlight the importance of epidemiological aspects of intrahepatic cholestasis of pregnancy. Material and method. All relevant information was obtained from literature review from the open access databases. Results. Recent studies suggest that the prevalence of ICP ranges from 0.5 to 1.0% in global population, although its incidence varies with ethnic subgroups and geographical distribution. Rates of obstetric cholestasis are high in South America, especially in Chile, with a reported prevalence rate of 12.6-22.1% depending on the ethnic population. Also, these rates have fallen to 1.5% - 4% in recent studies, possible due to changes in diagnostic criteria. Higher rates in Araucanian Indian origin women living in Chile were identified. The incidence of ICP in U.S.A is about 0.3%, based on a small number of studies. At the same time, recent study on a Latina population in Southern California determined a prevalence in this ethnic subgroup of 5.6%, which is considerably higher than previously reported. The incidence of ICP in Europe is lower - 1% ranging insignificantly for many years. It is more common for Finland, Sweden and Portugal population, where incidence of ICP varies between 1 and 2%, comparing with France, where prevalence has been reported to be around 0.2%. At the same time it has been reported an overall incidence of 0.7% in the South Birmingham area of UK. In this study, it was found a significantly higher incidence of ICP in Asian women of Pakistani (1.46%) and Indian (1.40%) origin. A retrospective clinical audit review undertook in Australia, sample size - 43 557 pregnancies reported the overall prevalence of ICP being 0.7% (319 cases). Also high rates of ICP in Caucasian (53.6% cases) and South Asian (22.6% cases) ethnicity were registered. In general, population a higher incidence is observed in twin pregnancies (20%-22%) and in women who took in vitro fertilization medication (2.7% vs 0.7%). At the same time, authors suggest that obstetric cholestasis is more common in women over the age of 35 years. Conclusions. Despite the fact that the global incidence of ICP is up to 1% the researches presented in this review draw special attention to wide variation due to different geographical location and ethnicity, further research is needed with detection of patients at high risk.