Objective To investigate the expression level and clinical significance of circular RNAs(circRNAs)in serum extracellular vesicles(EVs)of patients with recurrent spontaneous abortion(RSA).Methods The serum samples from 3 RSA patients and 3 nor-mal pregnant women(controls)visited our hospital from May 2021 to March 2023 were collected and the gene expression profiling chips were used to screen for differentially expressed circRNAs in serum EVs.Ten RSA patients and 10 normal pregnant women were enrolled in a training set and 80 RSA patients and 64 normal pregnant women were enrolled in a validation set.Real-time quantitative polymerase chain reaction(qRT-PCR)was used to detect the levels of differentially expressed circRNAs between the two groups.The predictive value of differentially expressed circRNAs for RSA was evaluated by the receiver operating characteristic(ROC)curve.Results A total of 57 563 circRNAs in serum EVs were detected by the gene expression profiling chips.Compared with the control group,3 516 circRNAs were differentially expressed in RSA patients,including 2 377 up-regulated and 1 139 down-regulated.The de-tection results of qRT-PCR in the training set and validation set showed that the expression levels of hsa＿circ＿0054403 in serum EVs of RSA patients(2.07[1.00,6.68])was significantly higher than that in the control group(1.00[0.42,1.46],U=1 239,P＜0.01),while those of hsa＿circ＿0020897(0.33[0.11,1.40]vs 1.00[0.46,3.66],U=1 712,P＜0.01)and hsa＿circ＿0072745(0.49[0.22,1.60]vs 1.00[0.51,7.93],U=1 714,P＜0.01)were significantly lower than that in the control group.The ROC curve showed that the hsa＿circ＿0054403,hsa＿circ＿0020897,and hsa＿circ＿0072745 in serum EVs had high predictive value for RSA.Their AUCROC were 0.758,0.666,and 0.664,respectively,and the corresponding sensitivity and specificity were 47.5% and 100.0%,50.0% and 81.2%,and 62.5% and 70.3%,respectively.When the three circRNAs were combined,it's AUCROC,sensitivity,and specificity were 0.842,73.7%,and 79.7%,respectively.Conclusion The hsa＿circ＿0054403,hsa＿circ＿0020897,and hsa＿circ＿0072745 in serum EVs of RSA patients are abnormally expressed,which may serve as the potential markers for predicting RSA.

Objective To investigate the expression level and clinical significance of circular RNAs(circRNAs)in serum extracellular vesicles(EVs)of patients with recurrent spontaneous abortion(RSA).Methods The serum samples from 3 RSA patients and 3 nor-mal pregnant women(controls)visited our hospital from May 2021 to March 2023 were collected and the gene expression profiling chips were used to screen for differentially expressed circRNAs in serum EVs.Ten RSA patients and 10 normal pregnant women were enrolled in a training set and 80 RSA patients and 64 normal pregnant women were enrolled in a validation set.Real-time quantitative polymerase chain reaction(qRT-PCR)was used to detect the levels of differentially expressed circRNAs between the two groups.The predictive value of differentially expressed circRNAs for RSA was evaluated by the receiver operating characteristic(ROC)curve.Results A total of 57 563 circRNAs in serum EVs were detected by the gene expression profiling chips.Compared with the control group,3 516 circRNAs were differentially expressed in RSA patients,including 2 377 up-regulated and 1 139 down-regulated.The de-tection results of qRT-PCR in the training set and validation set showed that the expression levels of hsa＿circ＿0054403 in serum EVs of RSA patients(2.07[1.00,6.68])was significantly higher than that in the control group(1.00[0.42,1.46],U=1 239,P＜0.01),while those of hsa＿circ＿0020897(0.33[0.11,1.40]vs 1.00[0.46,3.66],U=1 712,P＜0.01)and hsa＿circ＿0072745(0.49[0.22,1.60]vs 1.00[0.51,7.93],U=1 714,P＜0.01)were significantly lower than that in the control group.The ROC curve showed that the hsa＿circ＿0054403,hsa＿circ＿0020897,and hsa＿circ＿0072745 in serum EVs had high predictive value for RSA.Their AUCROC were 0.758,0.666,and 0.664,respectively,and the corresponding sensitivity and specificity were 47.5% and 100.0%,50.0% and 81.2%,and 62.5% and 70.3%,respectively.When the three circRNAs were combined,it's AUCROC,sensitivity,and specificity were 0.842,73.7%,and 79.7%,respectively.Conclusion The hsa＿circ＿0054403,hsa＿circ＿0020897,and hsa＿circ＿0072745 in serum EVs of RSA patients are abnormally expressed,which may serve as the potential markers for predicting RSA.

Objective To investigate the expression level and clinical significance of hsa_circ_0005075 in serum extracellular vesicles(EVs)of patients with recurrent spontaneous abortion(RSA).Methods Fourteen RSA patients and 14 normal pregnant women from the Department of Obstetrics and Gynecology,Qilu Hospital of Shandong University were enrolled in a training set,and 64 RSA pa-tients and 48 normal pregnant women were enrolled in a validation set.The expression levels of hsa_circ_0005075 in serum EVs were detected by the quantitative real-time PCR(qRT-PCR),and their correlation with clinical pathological parameters of RSA patients were analyzed.Serum anti-thyroid globulin antibody(A-TG)and anti-thyroid peroxidase antibody(A-TPO)were detected by the elec-trochemiluminescence assay.Serum anticardiolipin(ACA)IgA,IgG,and IgM antibodies and anti-β2 glycoprotein 1(β2GP1)IgA,IgG,and IgM antibodies were determined by the chemiluminescence immunoassay.The correlation of these autoantibodies with the lev-els of hsa_circ_0005075 in serum EVs was analyzed by the Pearson correlation.The clinical application value of hsa_circ_0005075 in the diagnosis of RSA was evaluated by the receiver operating characteristic(ROC)curve.Results The detection results of the training set showed that the expression levels of hsa_circ_0005075 in serum EVs of RSA patients(7.69[4.74,42.15])were significantly high-er than that in normal pregnant women(1.02[0.51,4.23],U=28,P＜0.01].Similarly,in the validation set,the expression levels of hsa_circ_0005075 in RSA patients(4.96[1.73,8.89])were also significantly higher than that in normal pregnant women(1.00[0.24,2.96],U=693,P＜0.01).The ROC curve showed that hsa_circ_0005075 in serum EVs had good diagnostic value for RSA(AUCROC=0.774),with 70.3%of sensitivity and75.0%of specificity.In addition,the expression level of hsa_circ_0005075 in serum EVs was significantly correlated with A-TPO(r=0.298,P＜0.05).Conclusion The hsa_circ_0005075 in serum EVs is highly ex-pressed in RSA patients,which may have a potential differential diagnostic value for the diagnosis of RSA.