RESUMO
Objective To study the expression situation of matrix metalloproteinase-9(MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the endometrium of women with unexplained infertility and normal endometrium, and to explore the relationship between MMP-9/TIMP-1 expres-sion and unexplained infertility. Methods Immunohistochemieal assay(SP method) was employed to deteet the expression of MMP-9/TIMP-1 in 20 cases of impaired endometrium(unexplained infertility group,endometrial plantation window phase)and 20 cases of normal endometrium(heahhy control group). Results There were different levels of MMP-9/TIMP-1 expression in kytoplasms of glandular epicytes and stromal cells of all endometrial samples. The expression of MMP-9/TIMP-1 was signifi-cantly weaker in unexplained infertility group than that in healthy control group(P＜0.05). Conclusion Low expression of MMP-9/TIMP-1 in the endometrial plantation window phase may be one of impor-tant factors for unexplained infertility.