Expression of MMP-2、MMP-9 and TIMP-1 in endometrium of PCOS patients during the implantation window phase and its clinical significance

Objective To investigate the expression of matrix metalloproteinase(MMP)-9, MMP-2 and matrix metalloproteinase inhibitor-1(TIMP-1) in endometrium of polycystic ovary syndrome(PCOS) patients during the implantation window phase, and to explore its significance.

Methods A total of 12 patients with PCOS who received post ovulation induction treatment(PCOS group) and 15 patients with infertility due to male factors and normal menstruation(control group) were selected.The expressions of MMP-9, MMP-2 and TIMP-1 proteins in endometrial tissue of the two groups on the seventh day after ovulation were detected.The pathology image analysis technology was employed to conduct the semi-quantitative analysis.

Results The expressions of MMP-9, MMP-2 and TIMP-1 in the two groups in endometrium were positive, and the brown granule cell pigmentation was found in the glandular epithelial cells and stromal cells cytoplasm, especially in the former ones.The expressions of MMP-2, MMP-9 and TIMP-1 in endometrial glandular epithelium in PCOS group were significantly lower than those in control group(P < 0.01), and the expression of MMP-9 in endometrial stroma was also lower than that in control group(P < 0.05).

Conclusions The low expression of MMP-9, MMP-2 and TIMP-1 in the implantation window phase of endometrium may be one of the causes of low pregnancy and high abortion rate in PCOS patients undergoing ovulation induction treatment.