A randomised controlled trial assessing ovarian reserve after laparoscopic ethanol sclerotherapy of ovarian endometrioma compared to standard treatment of surgical excision of endometrioma.

Secondary outcomes will include endometrioma recurrence, symptomatology and inflammatory environment.

Participants with endometrioma(ta), identified on imaging, who are opting for surgical management of endometriosis will be randomly allocated to laparoscopic ethanol sclerotherapy of endometrioma or laparoscopic surgical excision of endometrioma(ta). Any concurrent endometriosis identified at surgery will be excised as per routine care.

Ovarian reserve will be assessed by serum anti-Mullarian hormone (AMH) and antral follicle count (AFC), recurrence will me assessed by transvaginal ultrasound, symptomatology will be assessed by EHP-30 questionnaires and changes in inflammation assessed in serum and endometrial biopsy.

Each participant will be followed up for a total of 24 months from surgery.

Inclusion Criteria:

• Female (XX genotype, assigned female at birth)
• Age 18-40
• Finding of suspected uni- or bi-lateral ovarian endometrioma(ta) of ≥ 2cm on TVUSS and/or pelvic MRI scan (TVUSS, a uni- or multi-locular ovarian cystic lesion with low level echoes and diffuse homogeneous ground glass appearance; MRI any of, ovarian lesion hyperintense T1 without loss of signal on T1 fat-suppressed images, hypointense T2 exhibiting shading sign and/or T2 dark spot sign, variable restricted diffusion on DWI)
• Appropriate to be listed for laparoscopic excision of endometrioma (Endometrioma ≥2cm, pain symptoms attributable to endometriosis where medical management is unsuccessful or unacceptable to the patient, to facilitate ART)

Exclusion Criteria:

• Postmenopausal status
• Suspicion of malignancy
• Unable to undergo TVUSS
• Declines to take part in the study
• Unable to understand verbal or written information in English
• Lack of capacity to consent at the point of recruitment
• Known safeguarding issues

Ultra-sonographer