Study On The Relationship Between Low Expression Of PAPP-A In Early Pregnancy And Placental Ischemic Disease

Objective: To explore the risk of very low PAPP-A level in first trimester for ischemic placental disease.Method: Search of Pubmed,Embase,Cochrane library(inception-June,30 2017)for studies about very low PAPP-A level in first trimester and ischemic placental disease.(1)According to the inclusion and exclusion criteria,data of the included studies were extracted.Quality of these studies were assessed by the Newcastle-Ottawa Scale.(2)Meta-analysis was performed by Review Manager 5.3 software.Results: Twenty-six studies including 558381 pregnancies.Among pregnancies with PAPP-A level<5th,the risk for SGA<10th(OR=2.45,95%CI:2.31~2.59)? SGA<5th(OR=2.87,95%CI:2.58~3.18)?PE(OR=1.96,95%CI:1.71 ~2.25)?early-onset PE(OR=3.19,95%CI:2.31 ~4.40)?placental abruption(OR=1.69,95%CI:1.39 ~2.06).Among pregnancies with PAPP-A level<1st,the risk for SGA(OR=4.15,95%CI:3.69 ~4.68)? PE(OR=2.45,95%CI:1.73 ~3.48).PAPP-A<10th VS PAPP-A<5th VS PAPP-A<1st,SGA(OR=2.04 VS 2.45 VS 4.15),PE(OR=1.54 VS 1.96 VS 2.45).Conclusion: This study proves the possibility of PAPP-A as a marker of placental function.Pregnancies with very low PAPP-A level(particularly PAPP-A level<1st)are at higher risk of ischemic placental disease,who needs more surveillance during the gestation.At the meantime,this study demonstrates that PAPP-A could be a continuous variable in the combined prediction risks model of early-onset Preeclampsia,which promotes the secondary prevention of early-onset Preeclampsia.Objective: this study aims to establish a PAPP-A cut-off value in Chinese population that identifies ischemic placental disease(IPD).Method: We retrospectively analyzed 2077 spontaneous singleton pregnancies of Chinese women who underwent first-trimester combined Down's screening in our hospital and had delivery information available.PAPP-A levels were measured by perkin Elmer Wallac 1235 Auto DELFIA and converted to Mo M values correctd for maternal gestation and age for the local Chinese population.The performance of the prediction was expressed in sensitivity and specificity,while its clinical utility expressed in positive likehood ratio(LR+),and positive and negative predictive values(PPV and NPV).Results: The IPD was observed in 113 cases(5.4%),including 51 preeclampsia(2.5%),74 small for gestation age(3.6%)and 19 placental abruption(0.9%).The area under the curve of the receiver-operator characteristic curve for prediction of the ischemic placental disease using PAPP-A was 0.564(95%CI=0.520-0.690,P=0.003).Pregnancies with PAPP-A?0.2Mo M were at significant risk of IPD(LR+ 13.90)and SGA(LR+ 13.53),which was considered clinically useful.Conclusion: Chinese women with PAPP-A?0.2Mo M have a significant risk for IPD.More prospective cohorts were warranted and a compassion of the prediction performances by the same cut-off among different population would be interesting.