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Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
Doppler flow velocities in single umbilical arteries
N B Duerbeck1, M Pietrantoni, K L Reed
1Department of Obstetrics and Gynecology, University of Arizona School of Medicine, Tucson.
American Journal of Obstetrics and Gynecology
|October 1, 1991
Summary
Fetuses with a single umbilical artery may have normal Doppler flow velocities, despite risks of malformations and growth issues. Most fetuses studied showed normal systolic-to-diastolic ratios, indicating potential for typical fetal development.
Area of Science:
- Perinatology
- Fetal Medicine
- Medical Imaging
Background:
- Fetal compromise is linked to abnormal umbilical artery waveforms.
- Single umbilical artery (SUA) is associated with increased risks of malformations, mortality, growth retardation, and prematurity.
Purpose of the Study:
- To evaluate Doppler flow velocities in fetuses with a single umbilical artery.
- To assess the incidence of abnormal systolic-to-diastolic velocity ratios in SUA fetuses.
Main Methods:
- Doppler flow velocities were measured in 13 fetuses (9 singletons, 4 twins) with a single umbilical artery.
- Systolic-to-diastolic velocity ratios were analyzed.
- Incidence of anomalies and small for gestational age (SGA) were recorded.
Main Results:
- Five fetuses (38%) had anomalies, and six (46%) were small for gestational age.
- Three fetuses (23%) exhibited abnormally high systolic-to-diastolic velocity ratios.
- Notably, 77% of fetuses with SUA had normal systolic-to-diastolic ratios.
Conclusions:
- While some fetuses with SUA show abnormal Doppler ratios, a significant majority present with normal ratios.
- The presence of SUA warrants careful monitoring for anomalies and growth, irrespective of Doppler findings.
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