Application value of shear wave elastography in the diagnosis of pregnancy- specific liver disease and the prediction of adverse maternal and infant outcomes:a hybrid cross-sectional and prospective cohort study

Abstract Background Pregnancy-specific liver disorders (PSLD), including intrahepatic cholestasis of pregnancy (ICP), preeclampsia (PE), and hyperemesis gravidarum (HG), pose substantial risks to maternal and fetal health. Shear wave elastography (SWE) noninvasively quantifies liver stiffness, yet its value in PSLD remains undefined. We evaluated the diagnostic performance of SWE for PSLD and its subtypes, and assessed the independent predictive capacity of SWE-derived elasticity for incident PSLD and adverse maternal-fetal outcomes. Methods We conducted a hybrid cross-sectional and prospective cohort study of 341 pregnant women: 203 with uncomplicated pregnancies (111 in the first or second trimester) and 138 with PSLD (ICP, n = 43; PE, n = 50; HG, n = 45). All underwent standardized SWE and a serum liver panel. The 111 asymptomatic women were followed for incident PSLD, and the 138 patients with PSLD were followed for composite adverse outcomes. Diagnostic models integrating SWE (Emedian) and biochemistry were constructed, and independent associations were assessed by multivariable logistic regression. Results All SWE metrics were significantly higher in PSLD than in normal pregnancies (P < 0.001). In PSLD, Emedian correlated positively with ALT, AST, ALP, and TBA (r = 0.45–0.61, p < 0.001). The combined model (biochemistry + Emedian) yielded AUCs of 0.869 for PSLD, 0.918 for ICP, 0.931 for PE, and 0.793 for HG, outperforming biochemistry alone. Each 1-kPa increase in Emedian independently raised the risk of PSLD (OR = 4.01, 95% CI 2.77–5.82), ICP (OR = 5.36), PE (OR = 5.62), and HG (OR = 2.56). Among 111 women followed from early/mid-pregnancy, 19 developed PSLD; Emedian independently predicted incident PSLD (OR = 2.98, 95% CI 1.27-7.00; cutoff 3.69 kPa; AUC = 0.725). Among 138 patients with PSLD, 23 experienced adverse events; Emedian predicted the composite outcome (OR = 12.67, 95% CI 3.56–45.09; cutoff 6.58 kPa; AUC = 0.909). Conclusions SWE-derived liver stiffness provides independent diagnostic and prognostic value in PSLD. Combined with biochemistry, SWE markedly improves diagnostic accuracy and serves as an early predictor of incident PSLD and adverse maternal-fetal outcomes. Trial registration: Not applicable (observational study).