The Value Of Serological Indicators And MRI Diagnosis Of Placenta Previa Complicated With Placenta Accreta

Objectives:To investigate the value of maternal serum pregnancy associated plasma protein A（PAPP-A）,alpha-fetoprotein（AFP）,β-human chorionic gonadotropin（β-h CG）,unconjugated estriol（u E₃）and inhibin-A（Inhibin-A）in the first and second trimester combined with magnetic resonance imaging（MRI）diagnosis of placenta previa complicated with placenta accreta.Content:From January 01,2015 to October 31,2019 a total of 392 patients with placenta previa and Down’s screening in the first and second trimester who had delivery at the International Peace Maternal&Child Health Hospital affiliated to Shanghai Jiao Tong University of Medicine were selected as research subjects.According to the results of intraoperative findings and/or postoperative histopathology,they were divided into placenta accreta group（n=71）and without placenta accrete group（n=321）.Another 130 cases of who have normal placenta attachment position and without placenta accrete were control group.The basic clinical data and the results of the first and second trimester Down’s screening（including the MoM value of PAPP-A,β-h CG,AFP,u E3,Inhibin-A）of all patients were collected.And the results of ultrasound and MRI of placenta accrete group were collected.Methods:1.Retrospective analysis was performed.The basic clinical data were compared among three groups.2.The risk factors of placenta previa complicated with placenta accrera were analyzed by logistic regression analysis.3.The value of the indicators and which combined with the results of MRI was judged by receiver operating characteristic（ROC）and Youden index,and the relevant predictive boundary values were identified.Results:1.The placenta previa complicated with placenta accrera group were smaller than the control group at the gestation weeks.The placenta previa complicated with placenta accrera group were smaller than the simple placenta previa group at the gestation weeks.2.The times of cesarean section and complete placenta previa were independent risk factors for placenta previa complicated with placenta accreta.3.The median MoM value of PAPP-A,AFP in the placenta previa complicated with placenta accreta group were higher than that in the simple placenta previa group and the control group.The median MoM value of PAPP-A,AFP in the placenta increta（PI）group were significantly higher than that of the placenta accrete（PA）group.4.The boundaries values of placenta previa complicated with placenta accrata prediction as follows:PAPP-A 1.935 MoM and AFP 1.079 MoM.The sensitivity was 46.88%and 78.13%,respectively.The specificity was 83.98%and 55.77%respectively.The joint predicative factors of PAPP-A and AFP,the diagnostic sensitivity was 71.88%,which was higher than single test,the specificity was66.03%。5.The sensitivity of prenatal ultrasound and MRI for clinical diagnosis of placenta previa with placenta accreta was 31.7%and 41.4%,respectively.The specificity was 97.5%,96%.The ROC-AUC for ultrasound and MRI were:0.646,0.689, 0.679.Prenatal ultrasound combined with MRI,and AFP combined with prenatal ultrasound and MRI,the ROC-AUC were:0.677,0.761,0.811.Conclusion:1.The times of cesarean section and complete placenta previa were independent risk factors for placenta previa complicated with placenta accreta.2.The diagnosis of placenta previa complicated with placenta accreta,the detection of maternal serum PAPP-A in the first trimester and AFP in the second trimester have certain diagnostic significance.There is no statistical significance of the diagnosis of placenta previa complicated with placenta accreta in the detection ofb-h CG,u E₃,Inhibin-A in the second trimester.3.The maternal serum AFP value in the second trimester combined with MRI can improve the sensitivity and specificity of diagnosis of placenta previa complicated with placenta accreta,which are superior to single index detection and have certain diagnostic value.