Fertility Preservation in Women with Endometriosis: Indications, Timing, Techniques, and Reproductive Outcomes

Endometriosis is a chronic inflammatory disease frequently associated with infertility. Reproductive potential may be impaired by ovarian endometriomas, age-related decline, inflammatory and anatomical mechanisms, and ovarian surgery. This comprehensive narrative review summarises current evidence on fertility-preservation strategies in women with endometriosis, based on a structured literature search updated to 9 August 2026. Oocyte vitrification is the most frequently used and best-studied technique, while embryo cryopreservation may be considered according to individual circumstances, and ovarian tissue cryopreservation currently has a limited disease-specific role. Observational studies consistently show that increasing age and previous ovarian surgery are associated with fewer retrieved and mature oocytes, supporting counselling before ovarian surgery whenever feasible. Recent phenotype-stratified data further suggest that ovarian endometriosis is more consistently associated with reduced ovarian response than superficial or deep disease without ovarian involvement. Gonadotropin-releasing hormone antagonist and progestin-primed stimulation protocols both appear feasible, and repeated cycles may increase cumulative oocyte yield. Vitrified oocytes can survive warming and result in live birth; however, reproductive outcomes depend strongly on age and the number of oocytes available. Coexisting adenomyosis illustrates a limitation of gamete preservation because uterine factors may continue to affect implantation, miscarriage and later pregnancy outcomes. Recent follow-up data demonstrate that many women conceive spontaneously and that only a proportion return to use cryopreserved material. Consequently, the incremental benefit of preventive oocyte cryopreservation over expectant management and later fertility treatment remains unknown. Current evidence does not support systematic fertility preservation for all women with endometriosis. Early counselling and selective treatment should be considered, particularly in women with bilateral or recurrent ovarian disease, previous or planned ovarian surgery, and delayed reproductive plans.