The predictability of the small-for-gestational-age infant by real-time ultrasound-derived measurements combined with pulsed Doppler umbilical artery velocimetry.
During a 15-month period 373 level II ultrasound examinations were performed in 256 high-risk patients. In addition, pulsed Doppler spectral recordings of blood flow in the fetal umbilical arteries were made. A systolic/diastolic ratio was then calculated for each fetus. Real-time ultrasound-derived estimated fetal weight with the use of biparietal diameter and abdominal circumference was also calculated. The estimated fetal weights were categorized by placing them in a percentile for gestational age according to published nomograms. Complete birth data and outcomes were obtained in all patients. Both the systolic/diastolic ratio and ultrasound-estimated fetal weight grouped by percentile ranking for gestational age were highly predictive (p = 0.001) of babies who were subsequently born small for gestational age. Seventy-nine percent of the infants small for gestational age had umbilical artery systolic/diastolic ratios greater than or equal to 4, whereas only 21% had normal systolic/diastolic ratios. Forty-three percent of the infants who were small for gestational age had ultrasound-estimated fetal weights less than or equal to 10th percentile for the gestational age at which it was measured. Umbilical artery systolic/diastolic ratios, which reflect an increase in peripheral resistance in the placental circulation, showed a highly predictive and discriminatory index for the evaluation of the fetus suspected of having growth retardation.
Gaziano
E
E
Perinatal Center, Abbott-Northwestern Hospital, Minneapolis, MN 55407.
Knox
G E
GE
Wager
G P
GP
Bendel
R P
RP
Boyce
D J
DJ
Olson
J
J
D001724:Birth Weight; D001783:Blood Flow Velocity; D003971:Diastole; D005069:Evaluation Studies as Topic; D005260:Female; D005317:Fetal Growth Retardation / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D011379:Prognosis; D012212:Rheology; D013599:Systole; D014463:Ultrasonography / Q000379:methods*; D014469:Umbilical Arteries / Q000503:physiopathology*