Dr. Elena Santiago Romero

Vida Fertility Institute, Madrid, Spain

Abstract Title: Does the success rate change when comparing egg donation cycles using fresh or previously cryopreserved oocytes?

Biography:

Elena Santiago is a gynecologist after more than 11 years. She works at Vida fertility as ART and fertility expert and has a wide experience in treating foreign patients from all over the world. She has published in 9 different gynecological and fertility congresses.

Research Interest:

To determine whether the use of fresh versus cryopreserved oocytes does or does not influence the characteristics and results during egg donation treatments. Egg donation cycles with previously vitrified oocytes are an increasing treatment in ART. The endometrial preparation is easier and normally shorter in time for recipients than that with fresh oocytes where they must be synchronized with the donor. Thus, scheduling the day of the donation is easier and can be adapted to benefit the patient´s or the clinic´s schedule. Currently available data on cryopreserved donated oocytes are incomplete and, therefore, still not enough to claim equivalency between fresh and cryopreserved donor eggs.  We did a retrospective study of 200 egg donation cycles with homologous sperm microinjection and blastocyst stage transfer during 2022 and 2023 at our center. 151 cycles (75.5%) were performed with fresh donated oocytes and the remaining 49 cycles (24.5%) with previously cryopreserved donated oocytes. Despite the origin of the oocytes used (fresh/thawed) in the egg donation program, there were no differences in pregnancy outcomes. Due to the statistical design and sample size, more studies are needed to conclude that success rate does not change with the use of previously donated frozen eggs versus fresh ones. In egg donation cycles no differences were found in the number of embryos transferred, cryopreserved or in pregnancy rates using fresh or previously vitrified oocytes. Final outcomes were not affected by the differences in the percentages of retrieved oocytes or rates of embryo division obtained.