The expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 protein in cycling endometrium of patients with primary unexplained infertility

Objective To detect the expression of matrixmetalloproteinase-9(MMP-9) and tissue inhibitor of metalloproteinase-1 protein(TIMP-1) in cycling endometrium of patients with unexplained infertility,normal endometrium and normal early pregnant deciduas and explore the relationship between the expression of MMP-9 and TIMP-1 in unexplained infertility and normal pregancy.Methods Immunohistochememstry(S-P technique) and pathologic image semi-quantification were used to detect the expression of MMP-9 and TIMP-1 in endometrium of 30 unexplained infertility patients and 20 normal early pregnant deciduas and 20 normal endometrium.Results The expression of MMP-9 and TIMP-1 in normal early pregnant deciduas was the highest,showing significant difference as compared with other two groups(P0.05) The expression of MMP-9 and TIMP-1 was also high in normal endometrium as compared with other two groups(P0.05).But the expression of MMP-9 and TIMP-1 in endometrium of patients with unexplained infertility was significantly reduced as compared with other two groups(P0.05).Conclusion In unexplained infertility women,the low expression of MMP-9 and TIM P-1 protein in the implantation window phase may cause the failure of implantation and results in the infertility.