Surgery inevitably injures pelvic tissues and may provide a site for adherence of further endometrium. Much depends on the nature of the surgery. Surgeons use many operations to treat patients with chronic pelvic pain and endometriosis. A large randomised trial of LUNA (laser ablation of the uterosacral ligaments) showed no clear evidence of benefit though there may be some small, clearly-defined subgroups of women that may benefit from laser ablation of uterosacral nerves – though this is controversial.
“Truth” does not reside exclusively in randomised controlled trials and far too much weight has been attached to graded, taxonomies of “evidence-based medicine” by some organisations when “judgment” is what is badly needed (Sir Michael Rawlins in his Harveian oration, “De Testimonio”.