ObjectiveTo detect the proportion of splenic follicular helper T （Tfh） cells and their functionally related cytokine expression levels in the incomplete embryo implantation disorder （EID） model mice， and to explore the immunological mechanism of Tfh in infertility caused by embryo implantation disorder. MethodsSixteen female Kunming mice were randomly divided into two groups， with eight mice in each group. On day 4 of pregnancy， an incomplete EID mouse model was established by oral gavage of mifepristone suspension， while an equal volume of saline was administered to the control group. On day 8 of pregnancy， the mice were euthanized. Flow cytometry was used to detect the levels of Tfh cells in the spleen lymphocytes of both incomplete EID mice and normal control mice. qRT-PCR was performed to measure the mRNA levels of B-cell lymphoma 6 （Bcl-6） and C-X-C chemokine receptor type 5 protein （CXCR5） in the spleen lymphocytes of both groups. Western blot was employed to assess the protein expression levels of Bcl-6 and CXCR5 in the spleen lymphocytes of both groups. Serum levels of interleukin-4 （IL-4）， IL-6， and IL-21 were measured by ELISA. Immunohistochemistry （IHC） was used to observe the expression levels of progesterone receptor （PR）， Bcl-6， and CXCR5 proteins in the uterine endometrial tissue of mice in both groups. ResultsIncomplete-type EID mice had a reduced number of embryo implantation points and reduced endometrial PR expression. Flow assay results showed that the proportion of CD4⁺CXCR5⁺Tfh cells in splenic lymphocytes of incomplete-type EID mice was significantly higher than that of normal controls （P<0.05）. Compared with the normal control group， Bcl-6 and CXCR5 mRNA levels and protein levels were elevated in splenic lymphocytes of incomplete EID mice， with statistically significant differences （P<0.05）； serum IL-4， IL-6， and IL-21 levels were elevated in incomplete EID mice， and Bcl-6 and CXCR5 proteins in the endometrium were significantly elevated （P<0.05）. ConclusionThe increase of Tfh cells and their associated cytokines Bcl-6 and CXCR5 is associated with the development of incomplete EID， and may be involved in the development of female immune infertility.

Objective:To establish an oxidative stress injury model by using hydrogen peroxide (H 2O 2) to induce human ovarian granulosa cells COV434. Methods:Human ovarian granulosa cells line COV434 were randomly divided into 6 groups, control group was not treated, H 2O 2 groups were treated with H 2O 2 of 200 μmol/L, 400 μmol/L, 600 μmol/L, 800 μmol/L and 1 000 μmol/L for 0.5 h, 1 h, 2 h, 4 h and 6 h, respectively, and the cell viability was determined by CCK-8 method. The follow-up experiments were treated with different concentrations of H 2O 2 for 1 h. β-galactosidase staining was used to determine the degree of cell senescence. DCFH-DA fluorescence staining was determined by flow cytometry, and the level of reactive oxygen species (ROS) in cells was determined. JC-1 staining was used to determine the mitochondrial membrane potential of cells. Western blotting was used to determine the expression levels of apoptosis-related proteins Caspase-3 and Caspase-9. After the successful establishment of the model, in order to verify the usability of the cell model, the cells were pretreated with the antioxidant vitamin E for 12 h, followed by the addition of H 2O 2 for intervention, and the ROS level and mitochondrial membrane potential were measured. Results:The cell viability of the 200 μmol/L and 400 μmol/L groups decreased first and then increased compared with the control, and tended to be stable after 1 h of intervention, and there was no significant difference in cell viability at each time point (all P>0.05). When the concentration of H 2O 2 increased to 600 μmol/L, the cell viability gradually decreased with the treatment time and tended to stabilize after 1 h, and decreased significantly to nearly 50% ( P<0.001). When the concentration of H 2O 2 continued to increase to 800 μmol/L and 1 000 μmol/L, the cell viability gradually decreased with the treatment time and stabilized after 1 h, and decreased to less than 10% (all P<0.001). When the concentration of H 2O 2 was 200 μmol/L and 400 μmol/L, there was no significant difference in the ratio of β-galactosidase-positive cells and the relative ROS intensity after 1 h compared with the control (all P>0.05). When the concentration of H 2O 2 increased to 600 μmol/L, 800 μmol/L and 1 000 μmol/L, the ratio of β-galactosidase-positive cells and the relative ROS intensity increased significantly (β-galactosidase staining: P=0.011 at 600 μmol/L, P=0.003 at 800 μmol/L, P=0.005 at 1 000 μmol/L; the relative ROS intensity: P=0.002 at 600 μmol/L, P<0.001 at 800 μmol/L and 1 000 μmol/L). Compared with the control, the mitochondrial membrane potential of cells decreased gradually after intervention with different concentrations of H 2O 2, and was negatively correlated with H 2O 2 concentration (all P<0.001). There was no difference in the expression of Cleaved-Caspase-3 in the H 2O 2 group at 200 μmol/L compared with the control, and the expression was significantly increased at 400 μmol/L, 600 μmol/L, 800 μmol/L and 1 000 μmol/L (all P<0.001). The expressions of Caspase-3 and Caspase-9 were significantly increased in all H 2O 2 treated groups (all P<0.001). Compared with the model group, the relative ROS intensity of the vitamin E group was significantly reduced ( P=0.009), and the mitochondrial membrane potential was significantly increased ( P<0.001), but it could not be restored to the level of the control. Conclusion:Using 600 μmol/L H 2O 2 to continuously treat COV434 cells for 1 h can quickly establish a stable and effective oxidative stress injury model of human ovarian granulosa cells.

Objective:To establish an oxidative stress injury model by using hydrogen peroxide (H 2O 2) to induce human ovarian granulosa cells COV434. Methods:Human ovarian granulosa cells line COV434 were randomly divided into 6 groups, control group was not treated, H 2O 2 groups were treated with H 2O 2 of 200 μmol/L, 400 μmol/L, 600 μmol/L, 800 μmol/L and 1 000 μmol/L for 0.5 h, 1 h, 2 h, 4 h and 6 h, respectively, and the cell viability was determined by CCK-8 method. The follow-up experiments were treated with different concentrations of H 2O 2 for 1 h. β-galactosidase staining was used to determine the degree of cell senescence. DCFH-DA fluorescence staining was determined by flow cytometry, and the level of reactive oxygen species (ROS) in cells was determined. JC-1 staining was used to determine the mitochondrial membrane potential of cells. Western blotting was used to determine the expression levels of apoptosis-related proteins Caspase-3 and Caspase-9. After the successful establishment of the model, in order to verify the usability of the cell model, the cells were pretreated with the antioxidant vitamin E for 12 h, followed by the addition of H 2O 2 for intervention, and the ROS level and mitochondrial membrane potential were measured. Results:The cell viability of the 200 μmol/L and 400 μmol/L groups decreased first and then increased compared with the control, and tended to be stable after 1 h of intervention, and there was no significant difference in cell viability at each time point (all P>0.05). When the concentration of H 2O 2 increased to 600 μmol/L, the cell viability gradually decreased with the treatment time and tended to stabilize after 1 h, and decreased significantly to nearly 50% ( P<0.001). When the concentration of H 2O 2 continued to increase to 800 μmol/L and 1 000 μmol/L, the cell viability gradually decreased with the treatment time and stabilized after 1 h, and decreased to less than 10% (all P<0.001). When the concentration of H 2O 2 was 200 μmol/L and 400 μmol/L, there was no significant difference in the ratio of β-galactosidase-positive cells and the relative ROS intensity after 1 h compared with the control (all P>0.05). When the concentration of H 2O 2 increased to 600 μmol/L, 800 μmol/L and 1 000 μmol/L, the ratio of β-galactosidase-positive cells and the relative ROS intensity increased significantly (β-galactosidase staining: P=0.011 at 600 μmol/L, P=0.003 at 800 μmol/L, P=0.005 at 1 000 μmol/L; the relative ROS intensity: P=0.002 at 600 μmol/L, P<0.001 at 800 μmol/L and 1 000 μmol/L). Compared with the control, the mitochondrial membrane potential of cells decreased gradually after intervention with different concentrations of H 2O 2, and was negatively correlated with H 2O 2 concentration (all P<0.001). There was no difference in the expression of Cleaved-Caspase-3 in the H 2O 2 group at 200 μmol/L compared with the control, and the expression was significantly increased at 400 μmol/L, 600 μmol/L, 800 μmol/L and 1 000 μmol/L (all P<0.001). The expressions of Caspase-3 and Caspase-9 were significantly increased in all H 2O 2 treated groups (all P<0.001). Compared with the model group, the relative ROS intensity of the vitamin E group was significantly reduced ( P=0.009), and the mitochondrial membrane potential was significantly increased ( P<0.001), but it could not be restored to the level of the control. Conclusion:Using 600 μmol/L H 2O 2 to continuously treat COV434 cells for 1 h can quickly establish a stable and effective oxidative stress injury model of human ovarian granulosa cells.

Objective To explore the correlation between the characteristics of the endometrial microbiome in patients with recurrent implantation failure(RIF)and the subsequent transplantation outcomes.Methods A total of 438 RIF patients underwent embryo transfer again in our hospital were retrospective selection.According to the pregnancy status of the patients 8 weeks after embryo transfer,patients were divided into the pregnancy group(n=85)and the non-pregnancy group(n=353).The clinical data,characteristics and composition diversity of the endometrial microbiome were compared between the two groups.Binary Logistic regression was used to analyze the influencing factors,and the receiver operating characteristic(ROC)was employed to predict the efficacy of the influencing factors.The interaction between the above-mentioned risk factors and Shannon index in the subsequent transplantation outcomes of RIF patients was further analyzed.Results The levels of basal estradiol(E2),fasting insulin(Fins),total cholesterol(TC)and triglycerides(TG)were significantly higher in the non-pregnant group than those in the pregnant group(P＜0.05).Meanwhile,there were significant differences in the composition of endometrial microorganisms between the two groups(P＜0.05).Among them,the abundance of Fusobacterium phylum,the abundance of Bacillus genus and the α-diversity(Chao1,Shannon,Simpson)index all showed significant differences(all P＜0.05).Binary Logistic regression multivariate analysis showed that the abundance of Fusobacterium phylum increased(OR=1.628,95%CI:1.416-1.841),the abundance of Bacillus genus decreased(OR=0.725,95%CI:0.557-0.934)and E2 increased(OR=1.654,95%CI:1.343-1.965).The elevated insulin(OR=1.691,95%CI:1.393-1.980)and decreased Shannon index(OR=0.388,95%CI:0.075-0.697)were independent risk factors for failure after subsequent transplantation.ROC curve analysis showed that the area under the curve(AUC)of the Shannon index was 0.836(95%CI:0.782-0.890),with the highest predictive efficacy.There was significant interaction among the subgroups of Fusobacteria,Bacillus genus,E2 and insulin in Shannon index on the subsequent transplantation outcomes of patients with RIF.Conclusion The independent risk factors for subsequent transplantation failure in RIF patients can be used as sensitive indicators to predict the subsequent transplantation outcomes of RIF patients,and Shannon index has a higher clinical predictive value.

Objective To explore the correlation between the characteristics of the endometrial microbiome in patients with recurrent implantation failure(RIF)and the subsequent transplantation outcomes.Methods A total of 438 RIF patients underwent embryo transfer again in our hospital were retrospective selection.According to the pregnancy status of the patients 8 weeks after embryo transfer,patients were divided into the pregnancy group(n=85)and the non-pregnancy group(n=353).The clinical data,characteristics and composition diversity of the endometrial microbiome were compared between the two groups.Binary Logistic regression was used to analyze the influencing factors,and the receiver operating characteristic(ROC)was employed to predict the efficacy of the influencing factors.The interaction between the above-mentioned risk factors and Shannon index in the subsequent transplantation outcomes of RIF patients was further analyzed.Results The levels of basal estradiol(E2),fasting insulin(Fins),total cholesterol(TC)and triglycerides(TG)were significantly higher in the non-pregnant group than those in the pregnant group(P＜0.05).Meanwhile,there were significant differences in the composition of endometrial microorganisms between the two groups(P＜0.05).Among them,the abundance of Fusobacterium phylum,the abundance of Bacillus genus and the α-diversity(Chao1,Shannon,Simpson)index all showed significant differences(all P＜0.05).Binary Logistic regression multivariate analysis showed that the abundance of Fusobacterium phylum increased(OR=1.628,95%CI:1.416-1.841),the abundance of Bacillus genus decreased(OR=0.725,95%CI:0.557-0.934)and E2 increased(OR=1.654,95%CI:1.343-1.965).The elevated insulin(OR=1.691,95%CI:1.393-1.980)and decreased Shannon index(OR=0.388,95%CI:0.075-0.697)were independent risk factors for failure after subsequent transplantation.ROC curve analysis showed that the area under the curve(AUC)of the Shannon index was 0.836(95%CI:0.782-0.890),with the highest predictive efficacy.There was significant interaction among the subgroups of Fusobacteria,Bacillus genus,E2 and insulin in Shannon index on the subsequent transplantation outcomes of patients with RIF.Conclusion The independent risk factors for subsequent transplantation failure in RIF patients can be used as sensitive indicators to predict the subsequent transplantation outcomes of RIF patients,and Shannon index has a higher clinical predictive value.

Objective:To investigate the changes in follicular helper T cells(Tfh)and related cytokines in pe-ripheral blood and endometrial tissue of patients with unexplained recurrent implantation failure(URIF),and evalu-ate their predictive value for URIF.Methods:Sixty-four patients with URIF who visited the Reproductive Medicine Centre of the First Affiliated Hospital of Xinjiang Medical University from December 2020 to June 2022 were select-ed as the study group(URIF group),and 61 healthy women of childbearing age who visited our centre for male in-fertility in the same period were selected as the healthy control group(HC group).GSE microarrays of patients with recurrent implant failure(RIF)were collected in the Gene Expression Omnibus(GEO)database,and the pro-portion of different immune cells was identified using the CIBERSORT algorithm,and immune cell infiltration analy-sis and visualisation processing were performed using the Cibersort.R package.Peripheral blood samples and endometrial tissue samples were collected from the two groups of patients,flow cytometry was used to detect the proportion of Tfh cells in peripheral blood,enzyme-linked immunosorbent assay(ELISA)was used to detect serum levels of IL-4,IL-6,and IL-21,and immunohistochemical staining was used to detect the expression of CXCR5,Bcl-6,and IL-21 in endometrial tissue.Factors associated with URIF were analysed using multifactorial Logistic re-gression analysis.The predictive value of individual and combined tests for each indicator for URIF was analysed using the operating characteristic curve(ROC).The Drug Therapy Target Database(TTD)was used to predict potential therapeutic agents for URIF targeting IL-6 and IL-21,respectively.Results:The results of immune cell in-filtration in the GSE dataset in the GEO database showed that compared with normal controls,the numbers of ac-tivated memory CD4+T cells,Tfh,regulatory T cells(Treg),inactive macrophages,and resting dendritic cells were increased in the endometrial tissues of the patients with RIF(P＜0.05).The number of initial B cells,yδT cells,M2-type macrophages and activated dendritic cells were all decreased(P＜0.05).The levels of peripheral blood Tfh,IL-6 and IL-21 in the URIF group were all significantly higher than those in the HC group,and the difference was statistically significant(P＜0.05).Immunohistochemical staining results suggested that the expression of CX-CR5,Bcl-6 and IL-21 in the endometrium of patients in the URIF group was increased compared with that in the HC group(P＜0.05).Multivariate Logistic regression analysis showed that IL-6,IL-2,and Tfh were independent risk factors for the occurrence of URIF(OR＞1,P＜0.05).The area under the curve(AUC=0.974)of peripheral blood Tfh combined with IL-6 and IL-21 for diagnosis of URIF was higher than that predicted by each index alone,according to ROC analysis(P＜0.05).Five drugs targeting IL-6 or IL-21 with potential therapeutic effects on URIF were detected and screened through the TTD database.Conclusions:The levels of Tfh,IL-6 and IL-21 in the pe-ripheral blood of patients with URIF were abnormally elevated,and CXCR5,Bcl-6 and IL-21 were abnormally ex-pressed in the endometrium of patients with URIF,suggesting that Tfh cells and their cytokines are closely related to the occurrence and development of URIF.The combined prediction of these indicators has good diagnostic val-ue and may serve as a therapeutic target.

Objective:To investigate the association between programmed cell death protein 1 (PD-1) and its ligand PD-L1 and cytokines in patients with polycystic ovary syndrome (PCOS).Methods:Using the GSE54248 dataset from the GEO database, differentially expressed PD1/PD-L1 pathway-related genes in PCOS were identified and subjected to GO and KEGG pathway enrichment analysis. In this case-control study, totally 105 patients with PCOS (named PCOS group) and 109 non-PCOS patients (named control group) who were treated at the Reproductive Assisted Reproduction Center of the First Affiliated Hospital of Xinjiang Medical University from January 2022 to June 2023 were recruited. The QBPlex flow cytometry high-throughput multiplex assay was utilized to assess the peripheral blood levels of PD-L1, PD-L2, PD-1, and cytokines in PCOS group and control group. Pearson's method was used for correlation analysis.Results:In PCOS group, the PD-1 level in peripheral blood [2.890 (0.020, 4.540) ng/L] was significantly lower than that of control group [3.370 (2.460, 4.360) ng/L, P=0.008], the PD-L1 level [9.820 (8.860, 10.880) ng/L] was lower than that in control group [10.410 (9.700, 11.160) ng/L, P=0.001]. There was no significant difference in the expression level of PD-L2 between the two groups ( P>0.05). From the GSE54248 dataset, 26 differentially expressed genes were identified, primarily enriched in the PD-1/PD-L1 pathway, Th1 and Th2 cell differentiation, and pathways associated with the production of cytokines involved in inflammatory responses. Compared with control group, PCOS group exhibited a significant decrease in the peripheral blood concentrations of interleukin (IL)-5, IL-9, IL-25, IL-10, growth stimulation expressed gene 2 (ST-2), and Granzyme B, and a significant increase in IL-8, IL-1RA, and tumor necrosis factor-α (TNF-α) levels, with all differences being statistically significant (all P<0.05). PD-1 exhibited positive correlations with the levels of IL-1RA, ST-2, and TNF-α ( r=0.270, P=0.005; r=0.213, P=0.029; r=0.291, P=0.003), while it exhibited negative correlations with the levels of IL-9, IL-25, and Granzyme B ( r=-0.322, P<0.001; r=-0.211, P=0.031; r=-0.369, P<0.001). PD-L1 demonstrated positive correlations with the levels of IL-9, IL-25, and Granzyme B ( r=0.254, P=0.009; r=0.330, P<0.001; r=0.340, P<0.001), and a negative correlation with IL-10 level ( r=-0.373, P=0.009). Conclusion:The expression of PD-1 and PD-L1 in the peripheral blood of PCOS patients is down-regulated, which may be associated with an imbalance in Th1/Th2 cytokines and serve as potential molecular biomarkers for the treatment of PCOS.

Objective:To explore the role of methyltransferase-like 3 (METTL3) on endometrial decidualization.Methods:Bioinformatics was used to analyze the expression of 26 N6-methyladenosine (m6A) regulators in recurrent implantation failure (RIF), recurrent spontaneous abortion (RSA) and the decidualization of endometrial stromal cells. Using Medroxyprogesterone and Dibutyryl-cAMP to induce human endometrial stromal cell s (HESCs)decidualization, we examined changes in the expression of total m6A, METTL3, Forkhead framing protein O1 (FOXO1), and decidualization markers insulin-like growth factor binding protein 1 (IGFBP1) and prolactin in the control and decidualization group. Constructing HESC models with METTL3 interference using lentivirus, we used CCK-8 and Edu to detect proliferation in the negative control and knockdown METTL3 group. Lentiviral transfection was successfully followed by induction of decidualization, and we examined changes in the expression of FOXO1 and decidualization markers.Results:The results of bioinformatics analysis showed that the expression of METTL3 was significantly downregulated in the endometrium of patients with RIF and RSA ( P=0.014, P=0.016), while it was significantly upregulated in the endometrium with decidualization ( P=0.029). In vitro, induction of HESCs decidualization increased in the expression levels of total m6A, METTL3, and FOXO1 proteins in the decidualization group ( P=0.015, P=0.016, P=0.004). Knocking down METTL3 resulted in a decrease in FOXO1 protein expression in HESCs ( P=0.009). The CCK-8 and Edu results showed that the proliferation of HESCs was inhibited after knocking down METTL3. After inducing the knockdown of METTL3 in vitro, there was no statistically significant difference in the expression levels of IGFBP1 mRNA, PRL mRNA, and FOXO1 protein in HESCs compared with the negative control group (all P>0.05). Conclusion:In endometrial stromal cells, METTL3 can regulate the expression of FOXO1, promote the expression of IGFBP1 and PRL, and affect the decidualization of endometrial cells.

Objective:To investigate the association between programmed cell death protein 1 (PD-1) and its ligand PD-L1 and cytokines in patients with polycystic ovary syndrome (PCOS).Methods:Using the GSE54248 dataset from the GEO database, differentially expressed PD1/PD-L1 pathway-related genes in PCOS were identified and subjected to GO and KEGG pathway enrichment analysis. In this case-control study, totally 105 patients with PCOS (named PCOS group) and 109 non-PCOS patients (named control group) who were treated at the Reproductive Assisted Reproduction Center of the First Affiliated Hospital of Xinjiang Medical University from January 2022 to June 2023 were recruited. The QBPlex flow cytometry high-throughput multiplex assay was utilized to assess the peripheral blood levels of PD-L1, PD-L2, PD-1, and cytokines in PCOS group and control group. Pearson's method was used for correlation analysis.Results:In PCOS group, the PD-1 level in peripheral blood [2.890 (0.020, 4.540) ng/L] was significantly lower than that of control group [3.370 (2.460, 4.360) ng/L, P=0.008], the PD-L1 level [9.820 (8.860, 10.880) ng/L] was lower than that in control group [10.410 (9.700, 11.160) ng/L, P=0.001]. There was no significant difference in the expression level of PD-L2 between the two groups ( P>0.05). From the GSE54248 dataset, 26 differentially expressed genes were identified, primarily enriched in the PD-1/PD-L1 pathway, Th1 and Th2 cell differentiation, and pathways associated with the production of cytokines involved in inflammatory responses. Compared with control group, PCOS group exhibited a significant decrease in the peripheral blood concentrations of interleukin (IL)-5, IL-9, IL-25, IL-10, growth stimulation expressed gene 2 (ST-2), and Granzyme B, and a significant increase in IL-8, IL-1RA, and tumor necrosis factor-α (TNF-α) levels, with all differences being statistically significant (all P<0.05). PD-1 exhibited positive correlations with the levels of IL-1RA, ST-2, and TNF-α ( r=0.270, P=0.005; r=0.213, P=0.029; r=0.291, P=0.003), while it exhibited negative correlations with the levels of IL-9, IL-25, and Granzyme B ( r=-0.322, P<0.001; r=-0.211, P=0.031; r=-0.369, P<0.001). PD-L1 demonstrated positive correlations with the levels of IL-9, IL-25, and Granzyme B ( r=0.254, P=0.009; r=0.330, P<0.001; r=0.340, P<0.001), and a negative correlation with IL-10 level ( r=-0.373, P=0.009). Conclusion:The expression of PD-1 and PD-L1 in the peripheral blood of PCOS patients is down-regulated, which may be associated with an imbalance in Th1/Th2 cytokines and serve as potential molecular biomarkers for the treatment of PCOS.

Objective:To explore the role of methyltransferase-like 3 (METTL3) on endometrial decidualization.Methods:Bioinformatics was used to analyze the expression of 26 N6-methyladenosine (m6A) regulators in recurrent implantation failure (RIF), recurrent spontaneous abortion (RSA) and the decidualization of endometrial stromal cells. Using Medroxyprogesterone and Dibutyryl-cAMP to induce human endometrial stromal cell s (HESCs)decidualization, we examined changes in the expression of total m6A, METTL3, Forkhead framing protein O1 (FOXO1), and decidualization markers insulin-like growth factor binding protein 1 (IGFBP1) and prolactin in the control and decidualization group. Constructing HESC models with METTL3 interference using lentivirus, we used CCK-8 and Edu to detect proliferation in the negative control and knockdown METTL3 group. Lentiviral transfection was successfully followed by induction of decidualization, and we examined changes in the expression of FOXO1 and decidualization markers.Results:The results of bioinformatics analysis showed that the expression of METTL3 was significantly downregulated in the endometrium of patients with RIF and RSA ( P=0.014, P=0.016), while it was significantly upregulated in the endometrium with decidualization ( P=0.029). In vitro, induction of HESCs decidualization increased in the expression levels of total m6A, METTL3, and FOXO1 proteins in the decidualization group ( P=0.015, P=0.016, P=0.004). Knocking down METTL3 resulted in a decrease in FOXO1 protein expression in HESCs ( P=0.009). The CCK-8 and Edu results showed that the proliferation of HESCs was inhibited after knocking down METTL3. After inducing the knockdown of METTL3 in vitro, there was no statistically significant difference in the expression levels of IGFBP1 mRNA, PRL mRNA, and FOXO1 protein in HESCs compared with the negative control group (all P>0.05). Conclusion:In endometrial stromal cells, METTL3 can regulate the expression of FOXO1, promote the expression of IGFBP1 and PRL, and affect the decidualization of endometrial cells.