Prediction of placenta accreta by ultrasonography and color doppler imaging

Objective. To determine the accuracy of ultrasound and color flow Doppler to diagnose placenta accreta. Methods. Respectively, ultrasound images consistent with signs of placenta accreta (concomitant previa, numerous vascular lacunae, absent lower uterine segment between bladder-placenta, turbulent or complicated blood flow at the uteroplacental interface) were correlated with findings at the time of surgery and pathologic examination. Results. Over 64 months, 12 cases with suspected placenta accreta by ultrasound were studied. The median gestational age at first diagnosis was 25 weeks and 92% had a previa while all had at least one previous cesarean delivery. At surgery, 83% (10/12) had an adherent placenta requiring hysterectomy (eight accreta, one increta, and one percreta). There were two false positives (one complete previa, one low-lying placenta with vasa previa). Nine of 12 women (75%) required blood transfusions due to a mean hematocrit nadir of 22.7 +/- 4.6%. The mean number of packed red blood cell units transfused was 4.9 +/- 4.7 units (range 2-17 units). Conclusion. Sonography coupled with color-flow Doppler appears helpful in allowing antenatal diagnosis of accreta.