Umbilical Artery Flow Velocity Waveforms in High-Risk Pregnancy

A comparison of the effects of human alpha calcitonin gene‐related peptide and glyceryl trinitrate on regional blood velocity in man.

“…In this study we have used the pulsatility index (PI) and maximum (centre stream) velocity. PI is a quantification of the blood velocity waveform and is derived from the peak to peak amplitude of the waveform divided by the mean amplitude over the cardiac cycle (Gosling & King, 1974) and is directly proportional to downstream impedance to flow (Trudinger, 1987 …”

Melatonin supplementation alters uteroplacental hemodynamics and fetal development in an ovine model of intrauterine growth restriction

“…In addition, compromised pregnancies show a decrease in umbilical cord blood flow, which is due to a drop in umbilical blood flow velocity (51). Moreover, increased umbilical arterial pulsatility index and resistance index, which is contingent upon increased placental vascular resistance, are evident in both human and sheep compromised pregnancies (14,19,58). Low birth weight offspring from compromised pregnancies have increased incidences of adult onset diseases (6), poor growth rates, and lower daily rates of gross energy accretion (23).…”

Antenatal Diagnosis of Aberrant Umbilical Vessels

“…In our case, SUA was clearly observed connect ing to left internal iliac artery. In addition, to discern which is artery or vein precisely, additional examination using color and pulsed Doppler ultrasonography is useful, because SUA is often larger than normal artery, equaling its diameter to that of umbilical vein [ 16], Since Trudinger and Cook [17] first reported the ante natal diagnosis of DUA in 1988, a few cases of DUA have been described antenately. Most anomalies of umbilical vessels have been confirmed after delivery, but the dis tinction of DUA is difficult under the drained and col lapsed umbilical cord after delivery.…”

“…Most anomalies of umbilical vessels have been confirmed after delivery, but the dis tinction of DUA is difficult under the drained and col lapsed umbilical cord after delivery. Moreover, most ba bies with DUA have no external anomalies [9,17,18]. Therefore, DUA might be missed unless close antenatal investigation with ultrasonography was carried out.…”