Abstract: Objective To explore the diagnostic efficacy of ultrasound scoring method combined with human chorionic gonadotropin β (β-hCG), alpha fetoprotein (AFP), and creatine kinase (CK) on pernicious placenta previa (PPP) combined with placental implantation. 
Methods A total of 130 PPP patients were enrolled as the observation group, and 128 healthy parturients as control group. The observation group was divided into two groups according to presence of placental implantation, namely, implantation group (with placental implantation, n=97) and non-implantation group (without placental implantation, n=33). The ultrasound scoring method and the serum β-hCG, AFP, and CK levels were compared in each group. Spearman analysis was used to analyze the correlation of ultrasound scoring method and serum β-hCG, AFP, and CK with PPP and placental implantation. Receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of ultrasound scoring method, β-hCG, AFP, and PK levels for PPP with placental implantation. 
Results The ultrasound score method, β-hCG, AFP, and CK levels were higher in the observation group than in the control group (P＜0.05). The ultrasound score method, β-hCG, AFP, and CK in the implantation group were all higher than those in the non-implantion group (P＜0.05). The results of Spearman analysis showed that ultrasound scoring, β-hCG, AFP, and CK were positively correlated with PPP and placental implantation (r=0.566,0.537,0.439 and 0.524; P＜0.05). The results of ROC curve analysis showed that the area under the ROC curve (AUC) of ultrasound scoring method, β-hCG, AFP, CK and the combined diagnoses of the four indicators were 0.816, 0.877, 0.866, 0.758 and 0.956, respectively, and the diagnostic efficacy of the combined diagnosis of the four indicators for PPP with placental implantation was better than the single detection. 
Conclusion The combination of ultrasound scoring method with serum β-hCG, AFP, and CK has high diagnostic efficacy for PPP with placental implantation.

Key words: placenta previa, placenta accreta, diagnosis