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Pregnancy / Fetus



fetal doppler study

non-stress test (NST)
  • external monitoring for 20 minutes; poor specificity
  • >4 fetal heart accelerations (>15 bpm over baseline for 15 seconds) following fetal movement in fetus >34 weeks
  • no heart accelerations in immaturity, sleep, maternal sedation

contraction stress test (CST)
  • external monitoring after oxytocin or maternal breast stimulation
  • > 3 uterine contraction in 10 minutes; 50% specificity

uterine and umbilical artery waveform
  • elevated systolic:diastolic ratio = increased vascular resistance

fetal aortic flow volume
  • 185-246 ml/kg/min

see also:

Yong H. Hahn, MD  -  2 February 1995
Last updated:  1 October 2013


Related CHORUS documents:
intrauterine growth retardation (IUGR)
biophysical profile
IUGR: etiology
IUGR: phenotypes
fetal death
congenital infection: ToRCHS syndrome


Copyright © 2013, Charles E. Kahn, Jr.