Association of First-Trimester Hepatic Steatosis Index with Maternal and Perinatal Outcomes: A Prospective Observational Study

Background: Metabolic dysfunction associated steatotic liver disease (MASLD) is increasingly recognized among women of reproductive age and has been linked to adverse pregnancy outcomes. The Hepatic Steatosis Index (HSI) is a simple, non-invasive surrogate marker for hepatic steatosis, but its utility in early pregnancy for predicting adverse maternal and perinatal outcomes remains limited. Objective: To evaluate the association between the first-trimester Hepatic Steatosis Index and maternal and neonatal outcomes. Methods: This prospective observational study included pregnant women with a singleton gestation presenting in the first trimester (11–13 + 6 weeks) at a tertiary care teaching hospital. HSI was calculated using first-trimester alanine aminotransferase, aspartate aminotransferase, and body mass index. Participants were categorised into non-elevated (HSI < 36) and elevated (HSI ≥ 36) groups. Maternal outcomes included gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (HDP), mode of delivery, and preterm birth. Neonatal outcomes included birth weight, foetal growth restriction (FGR), gestational age at delivery, and neonatal intensive care unit (NICU) admission. Multivariate logistic regression was used to assess independent associations, adjusting for confounders. Results: Of 220 women included, 82 (37.3%) had elevated HSI. Women with elevated HSI had significantly higher odds of developing GDM (adjusted OR 2.72; 95% CI 1.09–6.80). Elevated HSI was also independently associated with a composite adverse maternal outcome (GDM and/or HDP) (adjusted OR 2.96; 95% CI 1.28–6.85). No consistent associations were observed between elevated HSI and adverse neonatal outcomes, although an adjusted association with foetal growth restriction was noted, with wide confidence intervals. Conclusion: Elevated first-trimester HSI is independently associated with adverse maternal metabolic outcomes, particularly gestational diabetes mellitus. HSI may serve as a practical early antenatal screening tool for identifying women at increased metabolic risk during pregnancy.