*4.1. Study Population*

For this study, tissue samples were collected in accordance with the protocols of the Endometriosis Marker Austria (EMMA) study, a prospective cohort study conducted at the Tertiary Endometriosis Referral Center of the Medical University of Vienna. Premenopausal women 18–50 years of age undergoing a laparoscopic procedure due to suspected endometriosis, infertility, chronic pelvic pain, benign adnexal masses or uterine leiomyoma were invited to participate in the EMMA study. Women who had acute inflammation, known or suspected infectious disease, chronic autoimmune disease or malignancy were excluded from the study. Ethics approval for this study was provided by the institutional ethics committee of the Medical University of Vienna (EK 545/2010). Verbal and written informed consent was obtained from each participant prior to inclusion into the study. The detailed baseline characteristics of the participants are summarized in Table S1. Briefly, from a total number of *n* = 95 participating women, *n* = 42 were defined as controls and *n* = 53 were patients suffering from endometriosis. The control group consisted of women undergoing laparoscopy for uterine fibroids, benign ovarian cysts, fallopian tube disorders or diagnostic laparoscopy due to unexplained infertility or chronic pelvic pain. Each participating woman contributed only one sample of eutopic endometrium and some of the women with endometriosis contributed samples of diverse types of endometriotic lesions. All tissue samples were collected during laparoscopic surgical intervention for

diagnosis and/or therapy of endometriosis. All samples were collected in accordance to Endometriosis Phenome and Biobanking Harmonization Project guidelines [50].
