Journal of Ultrasound in Medicine, Vol 8, Issue 4 183-185, Copyright © 1989 by American Institute of Ultrasound in Medicine
Doppler study of umbilical artery blood flow waveform. Should we use an instrument-adapted nomogram?
J. S. Abramowicz, J. Arrington, D. L. Levy and S. L. Warsof
Division of Maternal-Fetal Medicine, Eastern Virginia Medical School, Norfolk 23507.
Doppler studies of umbilical artery blood flow waveform are becoming an
accepted tool of antenatal estimation of fetal well-being. The S/D ratio of
the systolic peak (S) to the end-diastolic (D) frequency is the most
commonly used parameter. Nomograms relating S/D ratio to gestational age
have been published both for normal and pathologic pregnancies. Three
hundred twelve analyses of umbilical artery blood flow were performed by
continuous Doppler technology in normal, well-dated pregnancies using
either one of the following instruments: GE 3600 (GE) or Multigon 500A
(MG). Both instruments showed a decrease of S/D with GA, but, by use of a
nonpaired t test, a statistically significant difference was found between
the two machines. Data on the system used for a particular study should be
provided; nomograms for this particular instrument should be consulted and
the same machine should be employed for repeat testing in longitudinal
studies.
