Objective  To investigate the predictive value of prenatal ultrasonic graphic features combined with high risk factor score for placental implantation.

  Methods  A total of 120 patients confirmed as postpartum placenta previa were selected as study objects, and were divided into normal and adhesion group (n=77, normal placenta previa without implantation in 52 cases, adhesion placenta implantation in 25 cases) and implantation group (n=43, implantation placenta in 38 cases, penetration placenta implantation in 5 cases) according to caesarean section operation or pathological results as the diagnostic gold standard. Clinical data and typical ultrasonographic features of patients in the two groups were analyzed, and ultrasonographic feature combined with placental implantation risk factor score model was developed. Receiver Operating Characteristics (ROC) curve was used to analyze the diagnostic threshold values of the scale in the two groups, and the diagnostic sensitivity and specificity, positive and negative predictive values were calculated.

  Results  The boundary value of combined score scored 5. The diagnostic sensitivity and specificity were 81.4%, 94.8%, respectively, and the positive and negative predictive values were 89.7% and 90.1%, respectively.

  Conclusion  The combined scoring predictive model has high practical value in the diagnosis of placenta implantation.