Assessment of hepatic steatosis and liver stiffness using transient elastography in late pregnancy: a cross-sectional study

Background Steatotic liver disease is increasingly affecting younger individuals and women of reproductive age. Pregnancy provides an opportunity to identify maternal disease predispositions and to apply preventive interventions. The aim of this study was to establish reference ranges for vibration controlled transient elastography (VCTE) measurements in pregnancy and to examine factors associated with the presence of steatotic liver disease. Methods In this cross-sectional study, pregnant women were prospectively recruited at Harris Birthright Research Centre (London, UK) between 35 weeks and 36 weeks and 6 days of gestation. Women with a history of chronic liver disease, alcohol consumption of more than 14 units per week before pregnancy, multifetal gestation, or major fetal abnormalities were excluded. Controlled attenuation parameters (CAPs) and liver stiffness measurements (LSMs) were recorded using a FibroScan. Cutoffs for non-pregnant populations were used to determine the prevalence of hepatic steatosis (CAP ≥248 dB/m) and increased liver stiffness (LSM ≥6 kPa). The 90th percentile of each parameter was used to establish gestational cutoffs, and these values were used to investigate determinants of disease through multiple linear and logistic regression analyses. Findings Between Oct 1, 2023, and Jan 31, 2025, 5088 pregnant women were included. 501 (9·8%) of 5088 women had steatosis and 768 (23·2%) had increased liver stiffness according to the cutoffs for non-pregnant populations. The 90th percentile for CAP was 247 dB/m and for LSM was 6·8 kPa. In multivariable analysis using the gestational cutoffs, the factors associated with steatosis were history of type 2 diabetes (odds ratio 3·93, 95% CI 1·09–14·01) and weight in early pregnancy (1·05, 1·05–1·06). Factors associated with increased liver stiffness were type 1 diabetes (8·20, 2·37–26·40), type 2 diabetes (4·28, 1·29–13·40), pre-eclampsia (1·86, 1·19–2·82), and weight in early pregnancy (1·07, 1·01–1·14). Interpretation Our results suggest that obesity, pregestational diabetes, and pre-eclampsia might be associated with hepatic steatosis or increased liver stiffness in pregnancies assessed with VCTE, although due to the single-centre nature of our study, these findings need replication in larger multicentre studies. Future longitudinal studies targeting these subgroups are also needed to better understand the natural course of hepatic changes throughout pregnancy, the prognostic value of VCTE, and to evaluate postnatal interventions that could improve long-term liver health. Funding Fetal Medicine Foundation.