Early fetal circulation in pregnancies complicated by retroplacental hematoma.

The objective of this study was to investigate the effects in early gestation of retroplacental hematomas on Doppler indices measured in different fetal vascular districts and to relate these changes, if any, to the volume of hematoma and pregnancy outcome. Thirty-eight pregnancies complicated by bleeding and ultrasonographic findings of retroplacental hematomas were considered for this study. Menstrual age ranged between 9 and 14 weeks. Blood flow velocity waveforms were measured in the umbilical artery, descending aorta, middle cerebral artery, and inferior vena cava. The pulsatility index in arterial vessels was calculated as well as the percentage reverse flow in the inferior vena cava. The values obtained were compared to previously constructed reference limits. No significant differences were found for any of the Doppler indices when the values obtained in pregnancies complicated by retroplacental hematomas were compared to the reference limits. Furthermore no significant relationships were found between the Doppler indices and either the size of hematoma or pregnancy outcome. In conclusion, retroplacental hematoma does not induce hemodynamic effects in the fetal circulation before 14 weeks, menstrual age. These data do not support the use of Doppler ultrasonography in early gestation for pregnancies complicated by bleeding and retroplacental hematomas.