Ultrasound in fetal growth restriction

Abstract Fetal growth restriction (FGR) is associated with increased perinatal morbidity and mortality. Its recognition requires differentiation from a constitutionally small-for-gestational-age (SGA) fetus. Based on the current AWMF S2k guideline, this CME review summarizes the ultrasound assessment and clinical management of suspected FGR. Accurate first-trimester dating, standardized fetal biometry, assessment of amniotic fluid volume, and detailed anatomical evaluation form the basis of diagnosis. Consensus-based criteria distinguish early FGR before 32 + 0 weeks’ gestation from late FGR at or beyond 32 + 0 weeks’ gestation. Multivessel Doppler assessment of the umbilical artery, middle cerebral artery, cerebroplacental ratio, and ductus venosus provides complementary information on placental resistance, fetal redistribution, and cardiovascular decompensation. Cardiotocography, including computerized analysis of short-term variation in early FGR, is used as part of multimodal surveillance and should not be interpreted in isolation. The review discusses appropriate monitoring intervals, indications for inpatient care, antenatal corticosteroids and fetal neuroprotection when preterm birth is anticipated, as well as gestational-age- and finding-dependent timing and mode of delivery. A practical clinical case illustrates the diagnostic pathway from abnormal fetal biometry to delivery planning.