Placental disease and abnormal umbilical artery Doppler waveforms in trisomy 21 pregnancy: A case-control study

Fetal vascular malperfusion and maturation defects are more common in trisomy 21 placentas. Abnormal umbilical artery Doppler waveforms are more common in T21 and are associated with maternal vascular malperfusion. Placental disease may explain the increased rate of intrauterine death in T21.