Objective  To determine the effectiveness of laparoscopic uterine nerve ablation (LUNA) for chronic pelvic pain in women with endometriosis and women with no laparoscopic evidence of endometriosis.

Design  A prospective double-blind randomised controlled trial (RCT).

Setting  Single-centre, secondary-level gynaecology outpatient service and tertiary-level pelvic pain and endometriosis outpatient service in Auckland, New Zealand.

Population  One hundred and twenty-three women undergoing laparoscopy for investigation and management of chronic pelvic pain, 56 with no laparoscopic evidence of endometriosis and 67 with endometriosis.

Methods  Women were randomised from the two populations, firstly those with no evidence of endometriosis and secondly those undergoing laparoscopic surgical treatment for endometriosis, to receive LUNA or no LUNA. Participant and assessor blinding was employed. Follow up for pain outcomes was undertaken at 24 hours, 3 months and 12 months.

Main outcome measures  Changes in non-menstrual pelvic pain, dysmenorrhoea, deep dyspareunia and dyschezia were assessed primarily by whether there was a decrease in visual analogue score for these types of pain of 50% or more from baseline and additionally whether there was a significantly different change in median visual analogue score. The numbers requiring further surgery or starting a new medical treatment for pelvic pain and complications were also measured.

Results  There was a significant reduction in dysmenorrhoea at 12 month follow up in women with chronic pelvic pain in the absence of endometriosis who underwent LUNA (median change in visual analogue scale (VAS) from baseline −4.8 versus−0.8 (P= 0.039), 42.1%versus 14.3% experiencing a successful treatment defined as a 50% or greater reduction in visual analogue pain scale for dysmenorrhoea (P= 0.045). There was no significant difference in non-menstrual pelvic pain, deep dyspareunia or dyschezia in women with no endometriosis undergoing LUNA versus no LUNA. The addition of LUNA to laparoscopic surgical treatment of endometriosis was not associated with a significant difference in any pain outcomes.

Conclusions  LUNA is effective for dysmenorrhoea in the absence of endometriosis, although there is no evidence of effectiveness of LUNA for non-dysmenorrhoeic chronic pelvic pain or for any type of chronic pelvic pain related to endometriosis.