Prolonged oral GnRH-antagonist administration before euploid embryo transfer in patients with endometriosis: a prospective randomized pilot non-inferiority trial.

RESEARCH QUESTION: Is oral administration of a gonadotrophin releasing hormone (GnRH) antagonist for 2 months before euploid embryo transfer in patients with endometriosis non-inferior to intramuscular administration of a long-acting GnRH agonist for a similar period?

DESIGN

Prospective randomized non-inferiority pilot trial of infertility patients with surgically diagnosed endometriosis. Thirty patients were randomized to receive either oral elagolix 200 mg twice daily for 56 days (group 1; n = 15) or an intramuscular depot preparation of leuprolide acetate 3.75 every 28 days (group 2; n = 15) before euploid embryo transfer.

RESULTS

No differences were found in baseline characteristics between the two groups. Nor were any differences found between the two groups in maximal endometrial thickness before embryo transfer (10.9 ± 2.8 mm versus 10.3 ± 2.0 mm; P = 0.54). Despite a trend towards transfer of a higher percentage of day-5 euploid blastocysts in group 2 (53% versus 80%), no differences were found in positive pregnancy tests (86.7% versus 93.3%; P = 0.54) or live birth rates between the groups (87% versus 80%; P = 0.62).

CONCLUSION

Administration of the oral GnRH antagonist elagolix in appropriate doses for 2 months in women with endometriosis before euploid embryo transfer yields highly encouraging outcomes that are equivalent to those achieved with parenteral administration of a GnRH agonist, which could make this a more desired approach in these patients.