The impact of maternal body mass index and weight changes in intrahepatic cholestasis of pregnancy: a scoping review

Purpose To map the available literature, investigate the association between maternal body mass index (BMI), gestational weight gain (GWG) and the development and/or severity of intrahepatic cholestasis of pregnancy (ICP), and identify knowledge gaps. Methods A scoping review was conducted in accordance with PRISMA-ScR guidelines. Systematic searches of PubMed and EMBASE were performed to identify studies published between 2000 and 2025 examining BMI and/or GWG in relation to ICP. Animal studies, case reports, and studies lacking relevant exposure or outcome data were excluded. Results Twenty studies were included. Findings on BMI were inconsistent, with most studies showing no clear association with ICP. Lower GWG was more consistently associated with ICP. Evidence regarding associations between BMI, GWG and ICP severity was limited. Conclusion The available evidence does not demonstrate a consistent association between maternal BMI and ICP. Lower GWG may be associated with ICP, but interpretation is limited by retrospective designs, study heterogeneity, variable measurement timing, and possible reverse causation. Prospective or register-based studies using standardized measures and biomarkers are needed to address knowledge gaps regarding the association between maternal weight-related factors and ICP.