Objective:The pathogenesis of endometriosis(EMT)was explored by detecting the relationship of progesterone receptors(PR)and apoptosis-associated factors with EMT.Methods:Immunohistochemical imaging analysis was used to quantify the expression of PR,Bcl-2 and Bax in ectopic and eutopic endometrium in patients with EMT.Results:Expressions of PR and Bcl-2 in eutopic endometrium are higher than those in ectopic endometrium(P<0.05).Expression of Bax in ectopic endometrium is higher than that in eutopic endometrium(P<0.05).There is no statistical difference of PR,Bcl-2 and Bax expression between proliferative and secretary endometrium.Conclusions:Either in proliferative or secretary phase,expressions of PR in eutopic endometrium are higher than those in ectopic endometrium,thus eutopic endometrium is more liable to proliferate in low level continuously,migrate and implant.Expressions of Bcl-2 and Bax in eutopic and ectopic endometrium have no relationship with endometrium cycling.The apoptosis of ectopic endometrium is weakened and its proliferative power is continuously enhanced.