Objective: To study the relation between the expression of matrix metalloproteinase-9(MMP-9) / tissue inhibitor of metalloproteinase-1(TIMP-1) protein in the implantation window endometrium phase and serum estradiol and progesterone.Methods: 31 women with regular ovulation were included to obtain endometrium samples in implantation window phase

and at the same time serum were abstracted from vein for E2 and P testing.Immunohistochemical analysis was applied to measure the expression of MMP-9/TIMP-1 protein in the implantation window.Analysis the correlationship between MMP-9/TIMP-1 and E2 and P.Results: The light dense of the expression of MMP-9 / TIMP-1 protein in the endometrium of implantation window were 0.163±0.025

0.143±0.015 respectively

and the corresponding serum E2

P were 182.153±45.774pg/ml

22.997±6.697ng/ml respectively.There was negative correlationship between MMP-9 and P(P<0.001)

no correlationship was found between TIMP-1 and P

neither was MMP-9/TIMP-1 and E2.Conclusion: MMP-9 and P were correlated negatively

however there was no correlationship were found between TIMP-1and P

and between MMP-9/TIMP-1 and E2.