PURPOSE: We aimed to determine fetal liver perfusion in PGDM and GDM pregnancies and to assess the relation of ductus venosus (DV) shunt fraction with adverse pregnancy outcomes.

METHODS: We conducted a prospective longitudinal observational study including 188 pregnant women: group I-patients with pregestational DM (PGDM, n = 86), group II-patients with gestational DM (GDM, n = 44), group III-control (n = 58). The patients included in the study underwent ultrasound examination at 30 +0-40 +0 weeks of pregnancy. We evaluated volumetric blood flow adjusted to EFW (Q, ml/min/kg) for umbilical vein, DV, left and main portal vein. The relative risk was calculated for adverse pregnancy outcomes.

RESULTS: In PGDM pregnancies, umbilical blood flow was redistributed to the fetal liver, increasing left portal and total liver volumetric blood flow (p < 0.001) compared with GDM and control groups. Pathological reduction in the DV shunt fraction (≤ 16.5%) was associated with an increased relative risk of preterm delivery (3.61 [95%CI 1.68; 7.71]), LGA-birth (1.64 [95% CI 1.26; 2.12]), neonatal adiposity (1.53 [95%CI 1.18; 1.98]), fetal hypoxia (3.47 [95%CI 1.34; 9.05]), emergency cesarean Sect. (1.93 [95%CI 1.26; 2.97]), and neonatal intensive care unit stay of more than 5 days (1.78 [95%CI 1.08; 2.93]).

CONCLUSION: Decreased DV shunt fraction reflects changes in fetal hemodynamics in PGDM-pregnancies and associated with an increased risk of adverse perinatal outcomes.