Data Analysis The investigators hypothesize that NBI will improve detection of endometriosis lesions thus improving the diagnosis of endometriosis. For the primary outcome of diagnostic yield, the reference standard will be the pathologic confirmation of excised lesions where any one lesion within an individual detected by either method will confirm the diagnosis of endometriosis. The investigators will address the detection of endometriosis by comparing the diagnostic yield of the white light/white light group versus the white light/NBI group. The investigators will use a McNemar's test for the proportion comparison, which accounts for the pairing of assessment within a participant and makes no assumptions about the distribution of samples. At the lesion level, the investigators will assess the average change in the number of lesions detected between the white light/white light group to the white light/NBI group using independent samples t-test. The investigators will also calculate and compare the sensitivities and false positive rates for the white light/white light group and the white light/NBI group. Pain across the study period will be assessed by comparing average change in pain score (using both the VAS and the EHP-30 scores) between the two groups. The difference in average pain change scores will be assessed using an independent samples t-test. Differences in average pain between baseline and follow-up will be assessed using paired t-tests.