Fertility preservation in women with endometriosis

Endometriosis is a chronic disease that can compromise fertility in up to 30-50% of affected patients, and it is estimated that patients affected by endometriosis represent about 10% of patients undergoing ART treatments. The hypothesized underlying mechanisms explaining infertility are various, but great attention has been given to the relationship between ovarian endometriomas and reduced ovarian reserve. Infertility in patients with endometriosis does not have univocal management, since surgical therapy can increase the chances of natural conception, but at the same time increases the risk of damage to the ovarian reserve. In some cases, IVF procedures should be considered instead of surgery, within a personalized strategy. It has therefore been proposed that patients with endometriosis are eligible for fertility preservation. This article is based on a critical review of literature on peer-reviewed article indexing databases including PubMed, Scopus and Medline, using as keywords: 'fertility preservation', 'oocyte vitrification', 'endometriosis', 'endometrioma', 'ovarian reserve' and 'in vitro fertilization'. Data regarding the feasibility of oocyte cryopreservation in patients with endometriosis have increased over recent years, indicating that these patients seem to have the same number of oocytes retrieved and IVF outcomes similar to those who perform fertility preservation for other indications. However, probably due to a reduced ovarian reserve, several cycles of ovarian stimulation may be needed to gather a suitable number of retrieved oocytes per patient. Age, ovarian reserve, and previous ovarian surgery are the main factors affecting the success of fertility preservation. Bilateral endometriomas, a history of unilateral endometrioma surgery with a contralateral recurrence, and preoperative reduced ovarian reserve are the most common indications for fertility preservation. The choice between primary surgery and ART is often complex, requiring a therapeutic strategy tailored to the patient's clinical characteristics and needs, such as age, type and severity of endometriosis lesions, presence of symptoms, surgical history, and desire for pregnancy. The development of endometriosis-related infertility and the severity of ovarian damage due to endometriosis lesions per se or their surgical treatment are difficult to predict, and data are lacking concerning which subgroups of patients with endometriosis might benefit most from fertility preservation. Women with endometriosis, and in particular women with bilateral ovarian endometriomas or recurrent surgery on the ovaries, should be advised about risk of ovarian reserve damage. Oocyte cryopreservation is an established technique that has been demonstrated as feasible and successful for these patients; however, the specific indications have not yet been established. There are no funding sources for the study and no conflicts of interest to declare.