Absent end-diastolic flow velocity waveforms in the umbilical artery - the subsequent pregnancy

Article Abstract:

Subsequent pregnancies may be normal in women who have had a previous pregnancy complicated by absent umbilical end-diastolic velocity. Absent umbilical end-diastolic velocity is an abnormality in blood flow associated with fetal growth retardation and an increased risk of perinatal death. Among 88 women who had a pregnancy with absent end-diastolic velocity, all were complicated by preterm delivery, 94% by growth retardation and 56% by perinatal mortality. Seventy-four percent of the women had a subsequent pregnancy without complications. None of the subsequent pregnancies ended in perinatal death, and none were complicated by delivery before 32 weeks of gestation. Only two subsequent pregnancies were complicated by absent umbilical end-diastolic velocity. Absent umbilical end-diastolic velocity is a condition that can be detected using Doppler ultrasonography. Women who have had a pregnancy complicated by absent umbilical end-diastolic velocity should undergo routine Doppler ultrasonography of the umbilical cord.

Blood flow, Pregnancy, Complications of, Pregnancy complications

---

Reduced placental villous tree elaboration in small-for-gestational-age pregnancies: relationship with umbilical artery Doppler waveforms

Article Abstract:

Abnormal placental development may contribute to intrauterine growth retardation. The placental blood vessel structure was analyzed for 15 term and 5 preterm placentas of appropriate weight for gestational age infants and 9 term and 7 preterm infants weighing below the tenth percentile for gestational age. Microscope slides from randomly selected blocks of placental tissue were made, structural content was analyzed, and calculations were made to ascertain total placental content. The volumes and surface areas of the terminal villi were reduced among placentas from growth retarded fetuses, especially among preterm growth-retarded fetuses. This reduction would restrict the surface area where maternal-fetal exchange of oxygen and nutrients could occur.

Placenta

---

Effect of placental embolization on the umbilical arterial velocity waveform in fetal sheep

Article Abstract:

Inadequate blood flow into the placenta can cause growth-retarded fetuses. The small arteries of the placenta, the organ of fetal nutrition, can be studied to determine the velocity of the flow of blood. Doppler ultrasonography, the use of high frequency sound to visualize internal structures, was used to determine the waveforms created by the flow of blood through the umbilical cord arteries in seven pregnant sheep. The arteries were artificially blocked off with microscopic plastic beads so that the velocity of the blood flow went from normal to zero. In six sheep the direction of blood flow reversed before the fetus died. These abnormal waveforms are similar to the waveforms produced in human growth-retarded fetuses.

Research, Usage, Ultrasound imaging, Maternal-fetal exchange, Arterial occlusions, Arterial occlusive diseases

Similar abstracts:

• Abstracts: Fetal acoustic stimulation in the early intrapartum period as a predictor of subsequent fetal condition. Vaginal birth after cesarean delivery in the twin gestation
• Abstracts: Effects of epidural block with lignocaine and lignocaine-adrenaline on umbilical artery velocity wave ratios. Haemodynamic changes in gestational proteinuric hypertension: the effects of rapid volume expansion and vasodilator therapy
• Abstracts: Does obstetric ethics have any role in the obstetrician's response to the abortion controversy? Prenatal informed consent for sonogram: an indication for obstetric ultrasonography
• Abstracts: Treatment with GnRH agonists before myomectomy and the risk of short-term myoma recurrence. Buserelin versus danazol in the treatment of endometriosis-associated infertility
• Abstracts: Antenatal microbiologic and maternal risk factors associated with prematurity. Maternal deaths associated with Clostridium sordellii infection

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.