Abstract: This study investigated the clinical value of prenatal ultrasonography in the diagnosis of placenta previa with placenta accreta. Seventy-two pregnant women with placenta previa were selected as clinical research subjects, and all of them unwent prenatal ultrasound examination. Among them, 37 pregnant women with placenta previa combined with placenta accreta (inplantation group) and 35 pregnant women with placenta previa only (control group) were compared. Analyzed the differences on sonographic features and ultrasonic scores of the two groups, and the value of the ultrasonic scores in the diagnosis of placenta previa combined with placenta accreta. In implantation group, the proportion of patients with placental tissue thickness ≥3.0 cm, the detection rate of recesses in placental parenchyma, the proportion of patients with intact retroplacental hypoechoic zone, the proportion of patients with the thickness of the thinnest part of the uterine basal layer ≤1.0 mm, and the patients with rough bladder surface, the proportion of patients with regular blood flow signals at the base of the placenta, and the detection rate of cervical and peripheral blood flow signals were all higher than those of the control group (P＜0.05). The prenatal ultrasound score of the implantation group was significantly higher than that of the control group (P＜0.05). The AUC value of the prenatal ultrasound score for the diagnosis of placenta previa combined with placenta accreta was 0.944. Prenatal ultrasound in pregnant women with placenta previa and placenta accreta has typical features such as increased placental tissue thickness and occurrence of placental intraparenchymal recesses. Prenatal ultrasound scoring has high sensitivity and specificity for the diagnosis of placenta previa complicated with accreta.

Key words: prenatal ultrasound, diagnosis, placenta previa, placenta accreta, receiver operating characteristic curve