Cell-free placental mRNA in maternal plasma to predict placental invasion in patients with placenta accreta

Objective: To evaluate whether measuring cell-free placental mRNA in maternal plasma improves the diagnostic accuracy of ultrasound and color Doppler in detecting placental invasion in patients at risk for placenta accreta. Methods: Thirty-five singleton pregnant women of more than 28 weeks of gestation and at risk for placenta accreta underwent ultrasound and color Doppler assessment. Cell-free placental mRNA in maternal plasma was measured using real-time reverse-transcription polymerase chain reaction. Patients were classified into 2 groups based on the findings at cesarean delivery and histological examination: women with placenta accreta (n = 7) and women without placenta accreta (n = 28). Results: The median MoM (multiples of the median) value of cell-free placental mRNA was significantly higher in patients with placenta accreta than in those without placenta accreta (6.50 vs 2.60; P<0.001. Moreover, cell-free placental mRNA was significantly elevated in patients with placenta increta and percreta than in those with simple accreta. Six false-positive results were found on ultrasound, all from patients without placenta accreta and an insignificant rise in cell-free placental mRNA levels. Conclusion: Measuring cell-free placental mRNA in maternal plasma may increase the accuracy of ultrasound and color Doppler in prenatal prediction of placental invasion in patients with suspected placenta accreta. (C) 2009 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.