Fetal growth restriction (FGR): composite ultrasound estimated fetal weight less than 10th percentile for gestational age.
Fetal growth potential (Gardosi): estimated fetal weight percentile is determined by multiple maternal figure and fetal characteristics.
Placental unit: the hemochorial combination of the placental bed (maternal vascular elements that have their own characteristics and manifest the whole maternal environment) and the placenta itself, where fetal vascular elements portray the individual interactive fetal and placental environments.
Multivessel Doppler surveillance: composite Doppler assessment of umbilical artery, middle cerebral artery, and ductus venosus waveforms from the fetal circulation and the maternal uterine artery waveform to evaluate fetal, maternal, and placental hemodynamic status.
Biophysical Profile Scoring: five-component system using electronic fetal heart rate/movement correlation and four ultrasound components—fetal breathing movement, fetal body/limb movements, fetal tone, and amniotic fluid volume—to assess immediate fetal well-being.
Integrated Fetal Testing: system incorporating both multivessel Doppler and Biophysical Profile Scoring to optimize management of complicated FGR pregnancies.
The regulation of fetal growth is complex. From the general instructions of racial and familial input to the sophisticated redirection of nutrient-rich blood in the regional fetal hepatic circulation, a myriad of hereditary, maternal, placental, fetal, and acquired effects govern fetal growth. So, while fetal growth restriction (FGR) is an indication of concern, the finding is the start of a diagnostic pathway, not its conclusion.
Ultrasound media are critical to diagnosis, investigation, monitoring, and management of FGR. This chapter explores the integration of fetal imaging, biometry, Doppler velocimetry, biophysical profile scoring, and fetal heart rate (FHR) analysis in FGR management. Given the complexity of the issue, however, it must be made clear that ultrasound alone is insufficient—integrated multiformat ultrasound is just one facet of that care. Comprehensive care of FGR requires coordination of maternal, fetal, obstetric, and neonatal resources at every level.
Second only to prematurity, FGR is a leading cause of perinatal mortality. Prematurity and FGR act synergistically, but even when gestational age is accounted for, FGR increases perinatal mortality 6 to 10 times.1 Neonatal morbidity is also often the product of interacting FGR and prematurity, but even term FGR carries the risk of perinatal asphyxia, abnormal circulatory responses, short-term decompensation, and permanent organ damage (Figure 10-1). The long-term consequences of fetal malnutrition and the sacrifices that it dictates are reflected in the Barker hypothesis.2 Expanding data indicate that fetal deprivation is the source of adult hypertension, diabetes, cardiac disease, immune abnormalities, some forms of cancer, and shortened lifespan.
Morbidity of small premature neonates may be from FGR, prematurity, or low birth weight. FGR cases (green bars) were matched with premature neonates of the same birth weight (±100 g BW, blue bars) and also with normally grown (AGA) infants of the same gestational age at birth (±1 week GA, red ...