Title:Fetal Aortic and Umbilical Doppler Flow Velocity Waveforms in
Pregnancy: The Concept of Aortoumbilical Column
Volume: 20
Issue: 1
Author(s): De Almeida Ana Beatriz*, Morais Ana Rita, Ferreira Miguel, Gaio Ana Rita and Guedes-Martins Luís
Affiliation:
- Department of Obstetrics and Gynecology, Centro Hospitalar Universitário de Santo António, University of Oporto,
Oporto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar, University of Oporto, Oporto, Portugal
Keywords:
Cardiovascular system, doppler ultrasound, fetal descending aorta, umbilical artery, flow velocity waveform, aortoumbilical column.
Abstract: Low impedance within the uteroplacental circulation is crucial for fetal development.
Flow velocity waveforms (FVW) have been established for the aortic and umbilical arteries in
low-risk pregnancies during the second half of pregnancy, but data regarding early gestation is
limited. Both vascular territories exhibit higher impedance patterns in pregnancies complicated
by fetal growth restriction (FGR), hypertensive disorders, fetal anemia, and chromosomal abnormalities.
Early identification of these complications is critical in obstetric practice, to reduce
perinatal morbidity and mortality through prevention and close antenatal surveillance. Available
data suggest that aortic and umbilical impedances follow the same variation pattern as pregnancy
progresses. This observation implies that both vessels may be considered as a single artery, referred
to as the “aortoumbilical column”. Our hypothesis posits that changes in the hemodynamic
pattern of this column could identify high-risk pregnancies, particularly those complicated by
preeclampsia, FGR, intrauterine fetal demise, fetal aneuploidies, and fetal anemia. Understanding
vascular embryogenesis and the FVWs of the aortic and umbilical arteries enables comprehension
of impedance changes throughout normal pregnancies. The continuous variation in impedance
along a single vessel supports our concept of the aortoumbilical column. Deviations
from the regular pattern could assist in identifying compromised fetuses during early pregnancy.
Further research on normal aortoumbilical column FVW and the development of reference charts
is necessary to consider this arterial column as a screening tool in clinical practice.