Doppler blood flow changes and placental morphology in pregnancies with third trimester hemorrhage.

Combined real-time ultrasound and pulsed Doppler ultrasound examinations were performed in 67 patients with third trimester hemorrhage and other symptoms related to placental abruption, starting from the onset of symptoms to delivery. In 52 of the cases, placental morphology was investigated by light microscopy. Thirteen patients were ultimately given the diagnosis abruptio placentae. None of the morphological placental changes considered had any statistical relationship to placental abruption. Patients with placental centrocotyledon hemorrhages and infarction more often had abnormal umbilical artery flow velocity waveforms at the onset of symptoms, and more frequent abnormal arcuate artery flow velocity waveforms were found among those with placental infarction alone. Abnormal flow velocity waveforms in the umbilical and arcuate arteries were associated with placental abruption, both at the onset of symptoms and at the final examination before delivery. The results indicate an increased risk for placental abruption if the arcuate and/or umbilical artery flow velocity waveforms are abnormal in patients with third trimester hemorrhage.