Related Experiment Video
Updated: May 29, 2026

Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
Betamethasone effects on umbilical arteries and ductus venosus Doppler velocity waveforms in growth-restricted
Juan Piazze1, Kathleen Comalli Dillon, Albana Cerekja
1Ospedale di Ceprano, V.le Regina Margherita, Ceprano, Italy. jjpiazze2000@hotmail.com
Unlabelled:
We studied intrauterine-growth-restricted (IUGR) fetuses with absent or reversed umbilical artery end-diastolic flow (EDF) velocity in order to evaluate the benefit of antenatal steroid therapy. Perinatal outcomes after betamethasone were evaluated where end diastolic flow returned (group I), compared with data from fetuses with persistent absent-reverse end diastolic(ARED) flow (group II).
Objectives/Methods:
We recruited sixty-four IUGR fetuses, 28-32 weeks' gestation, whose umbilical artery spectral tracings showed ARED flow and positive a-wave in the ductus venosus at admission.
Results:
Group I, 21 cases of restored EDF after betamethasone: Significant, persistent return of umbilical artery EDF flow and persistent ductus venosus a-wave were documented. Group II, 43 cases of persistent ARED flow: Persistent ARED flow in umbilical arteries and deterioration of ductus venosus waveform with significant, increasing pulsatility index and/or a-wave disappearance were documented. In group I, cardiotocographic alterations were delayed contrasted with group II, (p = 0.03). Neonatal complications in group II were eight cases of intraventricular hemorrhage; two cases of retinopathy of prematurity; three neonatal deaths, one fetal demise; and a higher incidence of neonatal respiratory distress syndrome.
Conclusions:
Betamethasone treatment may have beneficial effects on restoring end-diastolic umbilical artery velocimetry and precordial waveforms. These spectral Doppler changes are related to delayed cardiotocographic alterations and to better perinatal outcomes.
Related Concept Videos
Fetal Circulation
Two umbilical arteries transport blood from the fetus to the placenta. At the placenta, the blood absorbs oxygen and nutrients while simultaneously eliminating waste products. This oxygen-enriched and nutrient-rich blood then returns to the fetus through one...
Teratogenicity
Development of Blood Vessels
The initial formation of this system is facilitated by the small amount of yolk present in the ovum and yolk sac. Blood vessels originate from...

