Patients seen at the SLUCare Center for Endometriosis (including those with or without pain) undergoing laser excision surgery for known or suspected endometriosis will be recruited for the study.

Per the PI's standard surgical approach to endometriosis, all areas of abnormal peritoneum will be excised (removed).

After surgical excision has been performed, in order to provide standardized specimens for our research, a 3mm punch biopsy will be obtained from the excised peritoneum tissue. The 3 mm biopsy will be sent for research analysis, and the rest of the excised peritoneum tissue will be sent to histology (SSM) for evaluation and classification as having endometriosis or not. For each patient in the study, blood will also be collected to look for markers for endometriosis.

The study is investigator-initiated, prospective, comparative study. Laparoscopic surgery for endometriosis on patients presenting with pain, infertility or both will be performed by the principal investigator at St. Mary's Hospital. We will be collecting preoperative, operative and postoperative follow-up data on all patients recruited for this study based on comprehensive preoperative questionnaires, which includes data collection on pain scores (by VAS scales) and standardized QOL scales, and the 6-12 month follow questionnaire. The surgical approach in the treatment of endometriosis is by excision only, so that all lesions (abnormal areas of peritoneum) are excised resulting in tissue specimens that are classified at a histologic level, which is the gold standard way to diagnose the presence of endometriosis.

Inclusion Criteria:

• Patients seen at the Center for Endometriosis (including those with or without pain) who are undergoing excision surgery.
• Patients who are undergoing laser excision surgery for known or suspected endometriosis will be recruited for the study.
• Completed a preoperative questionnaire

Exclusion Criteria:

• prior bilateral salpingo-oophorectomy
• post natural menopause

Patients seen at the Center for Endometriosis (including those with or without pain) undergoing laser excision surgery for known or suspected endometriosis will be recruited for the study.