Endometriosis affects 6-10% of women in childbearing age. It is a heterogeneous disease with three different forms: superficial endometriosis (peritoneal), ovarian endometrioma and deep pelvic endometriosis (subperitoneal).

Surgical management of endometriomas is justified in cases of significant clinical symptoms (like pain), especially in cases of resistance to medical treatment. Currently, laparoscopic cystectomy surgery is the recommended technique to treat ovarian endometrioma. However, it is now well demonstrated that this surgery significantly reduces the ovarian reserve.

Ethanol sclerotherapy is an alternative technique used to treat ovarian endometriomas. Several studies demonstrated the effectiveness and safety of this treatment, particularly in terms of preserving fertility. Regarding these reassuring data, many clinicians changed their practices and propose this technique as a first-line surgery.

Ovarian reserve comprises two elements: size of the primordial follicle stock and quality of the ovocytes. Antimüllerian hormone (AMH) has been shown to be the best marker of fertility.

The aim of this study is to observe changes in AMH levels after endometrioma sclerotherapy. This study is conducted in the Hospices Civils de Lyon, in 3 different sites.

Inclusion Criteria:

• Patient in childbearing age from 18 to 42 years.
• Patient with uni- or bilateral endometrioma(s) without clinical and ultrasound criteria for ovarian carcinoma.
• A sclerotherapy is programmed.
• Patient affiliated to a social security scheme.
• Patient who gave consent for this research.

Exclusion Criteria:

• doubt about the endometriotic origin of the cyst
• suspect malignant ovarian disease.
• Pregnant or breastfeeding patient.
• Patient participating in other research with an exclusion period still in progress at the time of inclusion or those included in interventional research that interferes with the study protocol.
• Patient deprived of liberty by judicial or administrative decision.
• Patient (≥ 18 years old) under legal protection or unable to give consent.
• Patient does not speak French.