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Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
Umbilical artery waveform during bicycle exercise in normal pregnancy
J C Veille1, A E Bacevice, B Wilson
1Department of Reproductive Biology, Case Western Reserve University, Cleveland, Ohio.
Eighteen healthy pregnant women in the last half of gestation exercised to 85% of their predicted maximum heart rate on a bicycle ergometer. Pulsed Doppler flow studies before the exercise and during the recovery period were taken close to the umbilical artery's placental insertion site. The systolic-to-diastolic ratio (S/D) of the umbilical artery waveform did not change significantly during the period of observation. In three women, however, a significant increase in the S/D ratio occurred in the first few minutes post-exercise; this was due to a transient fetal bradycardia. In one woman, the S/D ratio remained high despite return of a normal fetal heart rate.
Eighteen healthy pregnant women in the last half of gestation exercised to 85% of their predicted maximum heart rate on a bicycle ergometer. Pulsed Doppler flow studies before the exercise and during the recovery period were taken close to the umbilical artery's placental insertion site. The systolic-to-diastolic ratio (S/D) of the umbilical artery waveform did not change significantly during the period of observation. In three women, however, a significant increase in the S/D ratio occurred in the first few minutes post-exercise; this was due to a transient fetal bradycardia. In one woman, the S/D ratio remained high despite return of a normal fetal heart rate.
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