The fetal cardiovascular response to antenatal steroids in severe early-onset intrauterine growth restriction.
OBJECTIVE
Our aim was to study the hemodynamic effects of betamethasone on fetuses with intrauterine growth restriction (IUGR) with absent or reversed end-diastolic (ARED) umbilical artery flow.


METHODS
Color/pulsed Doppler waveforms were obtained before and after intramuscular injections of betamethasone in 19 consecutive fetuses with IUGR/ARED and 6 control fetuses. Peak velocities and pulsatility index (PI) values were obtained from the umbilical (UA) and middle cerebral (MCA) arteries and intrahepatic umbilical vein (UV).


RESULTS
Ten ARED fetuses developed transient positive umbilical end-diastolic flow after steroids, whereas nine fetuses showed persistent ARED. The persistent ARED subgroup demonstrated increased UA and UV peak velocities after steroids, which may indicate fetal hypertension. Fetal death (n=2) and severe acidosis (n=2) were confined to the subgroup with persistent ARED.


CONCLUSIONS
Preterm IUGR/ARED fetuses exhibit divergent cardiovascular responses to prenatal steroids. Intensive Doppler-based fetal monitoring may identify a subset of fetuses prone to decompensation after maternal steroid administration.
Simchen
Michal J
MJ
Division of Maternal-Fetal Medicine, University of Toronto, Toronto, Ontario, Canada. michal_simchen@sheba.health.gov.il
Alkazaleh
Fawaz
F
Adamson
S Lee
SL
Windrim
Rory
R
Telford
Joyce
J
Beyene
Joseph
J
Kingdom
John
J
D000138:Acidosis / Q000209:etiology; D000328:Adult; D001623:Betamethasone / Q000494:pharmacology*; D001783:Blood Flow Velocity; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D005333:Fetus / Q000187:drug effects / Q000502:physiology*; D005938:Glucocorticoids / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008137:Longitudinal Studies; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D018615:Ultrasonography, Doppler, Color; D018617:Ultrasonography, Doppler, Pulsed; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D014655:Vascular Resistance / Q000187:drug effects / Q000502:physiology
D005938:Glucocorticoids; D001623:Betamethasone