MSERM – Egg Freezing Cracks up to be a Viable Fertility Preservation (FP) METHOD: Fifteen Years of Autologous Oocyte (AO) Thaw Outcomes at a Large UNIVERSITY-BASED Fertility Center

Track: Fertility Preservation
Poster : Fertility Preservation
Sarah Druckenmiller Cascante
Fellow NYU Langone Fertility Center
New York, New York

Objective: AO cryopreservation (cryo) is widely used for FP, but published thaw data is scarce. Our aim was to review our AO thaws. DESIGN: Retrospective cohort. MATERIALS AND

Methods: Patients (pts) who thawed AOs at our university-based fertility center from 2004-2019 were reviewed. Pts were excluded if cryo was performed for a medical indication, as research, due to lack of sperm, due to a natural disaster or in combination with embryos. Pts were also excluded if they had cancer or planned to use a gestational carrier. Outcomes included implantation (IR), spontaneous abortion (SABR) and ongoing pregnancy + live birth (LBR) rates. Statistics included Mann-Whitney U and Fisher’s exact tests, with p<0.05 as significant.

Results: We reviewed 468 pts (median age at first cryo 38y, range 27-46y), who underwent 677 cryos (89% at our center, 8% elsewhere, 2% at both), 523 thaws and 360 embryo transfers (ET). Cryo involved vitrification for 69%, slow freezing for 4% and both for 27% of pts. Median time between first cryo and first thaw was 4y. Overall AO cryo survival was 79%, M2 cryo survival was 80% and 2PN fertilization (fert) was 66%. 441 thaws (84%) led to ≥1 embryo for fresh ET, trophectoderm biopsy (TEBX) or cryo while 82 thaws (16%) led to no embryos for ET, TEBX or cryo. Of thaws with TEBX, 65% had ≥1 euploid embryo. 142 ETs (39%) were fresh, with 2% using rush biopsied embryos. 218 ETs (61%) were frozen, with 97% using biopsied embryos. In euploid ETs (n = 205), IR was 64%, SABR was 10% and LBR was 55%. In non-biopsied ETs (n = 146), IR was 28%, SABR was 14% and LBR was 32%. There were 8 mosaic and 1 aneuploid ET. See table for outcomes by age. In total, our pts have 155 babies (11 twin, 1 triplet) and 19 ongoing pregnancies (2 twin) from AO cryo. 51 pts (11%) have remaining frozen AOs and 117 (25%) have euploid or untested embryos.

Conclusions: AO cryo is a viable FP method and led to live birth in 32% of pts, comparable to our center’s 34% LBR per intended retrieval1 and the national 26% LBR per intended retrieval in pts of similar age (38-40y)2.

ASMR official sponsorship in the publications of the virtual ASMR conference October 17-21 October 2020