PGR and endometriosis: In contrast, eutopic endometrial tissue expression of PGR was reported to show no differences between endometriosis and control subjects, but lower expression in both glands and stroma of the ectopic lesion [27], while assessment of PGR transcript expression in eutopic endometrial tissue from women with endometriosis failed to exhibit differences in expression level compared to eutopic endometrium from infertile and fertile control subjects [28].