Role of uteroplacental and fetal Doppler in identifying fetal growth restriction at term

Identification of the fetus at risk of adverse outcome at term is a challenge to both clinicians and researchers alike. Despite the fact that fetal growth restriction (FGR) is a known risk factor for stillbirth, at least two thirds of the stillbirth cases at term are not small for gestational age (SGA) - a commonly used proxy for FGR. However, the majority of SGA fetuses are constitutionally small babies and do not suffer from adverse perinatal outcome. The cerebroplacental ratio (CPR) is emerging as a marker of failure to reach growth potential at term. CPR is an independent predictor of intrapartum fetal distress, admission to the neonatal unit at term, stillbirth, perinatal death and neonatal morbidity. Raised uterine artery Doppler resistance in the third trimester is independently associated with significantly lower birthweight and CPR. The combination of the estimated fetal weight, CPR and uterine Doppler in the third trimester can identify the majority of fetuses at risk of stillbirth.