MMP2 and endometriosis: As for the comparison of MMP-2 expression between ectopic endometrium in group 1 (with endometriosis) and eutopic endometrium in group 2 (control group), there was a significant difference between them (1.82 ± 0.27 IHC optical density score vs. 1.41 ± 0.34 in the control group, p = 0.001).