Objective To investigate the correlation between serum cytotoxic T lymphocyte associated pro-tein 4(CTLA4),high mobility group box 1(HMGB1)and the balance of helper T cell 17(Th17)/regulatory T cell(Treg),and to study their diagnostic significance for unexplained recurrent spontaneous abortion(URSA).Methods A total of 102 patients with URSA admitted to the hospital from September 2022 to September 2024 were selected as the URSA group,and another 80 healthy pregnant women who underwent prenatal examinations in the hospital during the same period were selected as the healthy group.The levels of serum CTLA4 and HMGB1 in the two groups were detected,the levels of Th17 and Treg in the two groups were detected,the Th17/Treg ratio was calculated,and the general data of the two groups were collected and recorded.Pearson was used to analyze the correlations between the levels of serum CLTA4 and HMGB1 and Th17,Treg,and Th17/Treg.logistic regres-sion was used to analyze the influencing factors of URSA occurrence.The receiver operating characteristic(ROC)curve was used to analyze the value of serum CTLA4 and HMGB1 levels in evaluating the occurrence of URSA.Results the serum CTLA4 level in the URSA group was lower than that in the healthy group,the HMGB1 level was higher than that in the healthy group,the Th17 level and Th17/Treg were higher than those in the healthy group,and the Treg level was lower than that in the healthy group(P<0.05).The serum CTLA4 level was nega-tively correlated with the Th17 level and Th17/Treg,and positively correlated with the Treg level(P<0.05).The level of HMGB1 was positively correlated with the level of Th17 and Th17/Treg,and negatively correlated with the level of Treg(P<0.05).Pregnancy frequency,serum CTLA4 level,serum HMGB1 level,Th17 level,Treg level,and Th17/Treg are independent influencing factors for the occurrence of URSA(P<0.05).The areas under the curve(AUC)of serum CTLA4 and HMGB1 levels and the combined evaluation of URSA by the two indicators were 0.841,0.787,and 0.908 respectively,and the Youden indices were 0.652,0.491,and 0.656 respectively.Conclusions The serum CTLA4 level is decreased and the HMGB1 level is increased in patients with URSA,which is related to the change of Th17/Treg balance.The levels of serum CTLA4 and HMGB1 have auxiliary diag-nostic significance for URSA.

Objective To investigate the correlation between serum cytotoxic T lymphocyte associated pro-tein 4(CTLA4),high mobility group box 1(HMGB1)and the balance of helper T cell 17(Th17)/regulatory T cell(Treg),and to study their diagnostic significance for unexplained recurrent spontaneous abortion(URSA).Methods A total of 102 patients with URSA admitted to the hospital from September 2022 to September 2024 were selected as the URSA group,and another 80 healthy pregnant women who underwent prenatal examinations in the hospital during the same period were selected as the healthy group.The levels of serum CTLA4 and HMGB1 in the two groups were detected,the levels of Th17 and Treg in the two groups were detected,the Th17/Treg ratio was calculated,and the general data of the two groups were collected and recorded.Pearson was used to analyze the correlations between the levels of serum CLTA4 and HMGB1 and Th17,Treg,and Th17/Treg.logistic regres-sion was used to analyze the influencing factors of URSA occurrence.The receiver operating characteristic(ROC)curve was used to analyze the value of serum CTLA4 and HMGB1 levels in evaluating the occurrence of URSA.Results the serum CTLA4 level in the URSA group was lower than that in the healthy group,the HMGB1 level was higher than that in the healthy group,the Th17 level and Th17/Treg were higher than those in the healthy group,and the Treg level was lower than that in the healthy group(P<0.05).The serum CTLA4 level was nega-tively correlated with the Th17 level and Th17/Treg,and positively correlated with the Treg level(P<0.05).The level of HMGB1 was positively correlated with the level of Th17 and Th17/Treg,and negatively correlated with the level of Treg(P<0.05).Pregnancy frequency,serum CTLA4 level,serum HMGB1 level,Th17 level,Treg level,and Th17/Treg are independent influencing factors for the occurrence of URSA(P<0.05).The areas under the curve(AUC)of serum CTLA4 and HMGB1 levels and the combined evaluation of URSA by the two indicators were 0.841,0.787,and 0.908 respectively,and the Youden indices were 0.652,0.491,and 0.656 respectively.Conclusions The serum CTLA4 level is decreased and the HMGB1 level is increased in patients with URSA,which is related to the change of Th17/Treg balance.The levels of serum CTLA4 and HMGB1 have auxiliary diag-nostic significance for URSA.