In 2012, oocyte cryopreservation was no longer deemed experimental by the American Society of Reproductive Medicine. Since then, awareness and utilization of planned oocyte cryopreservation has become much more widespread. However, little is known regarding current national trends and the rate of warming and utilization of cryopreserved oocytes. To assess national trends in planned oocyte cryopreservation, subsequent oocyte utilization and outcomes of oocyte warming cycles. Retrospective cohort study with data from all patients reported to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART-CORS) undergoing cryopreservation of autologous oocytes for fertility preservation only between the years 2014 and 2021 and all linked oocyte warming cycles. Statistical analyses were performed using linear regression tests. The number of patients undergoing planned oocyte cryopreservation has increased exponentially, with 4,153 patients in 2014 compared to 16,436 in 2021 (p42 years (p<0.01). Of patients who returned for oocyte warming, 78.5% (n=669) obtained a usable embryo while 21.5% (n=183) had no useable embryos. Of those with useable embryos, 64.2% (n=547) had a fresh embryo transfer, 46.1% (n=393) had embryos for cryopreservation, and only 14.3% of patients (n=122) opted for a freeze-all approach. Of the 393 patients with cryopreserved embryos, 115 (29.3%) returned for a frozen embryo transfer. The cumulative live birth rate of all patients undergoing oocyte warming was 28.9%, with live birth rate decreasing with increasing age at time of oocyte cryopreservation. Since the availability of oocyte cryopreservation reporting for fertility preservation only, planned oocyte cryopreservation has increased exponentially. Mean age at time of oocyte retrieval has decreased, reflecting interest in the procedure amongst younger patients, but there has been minimal change in distribution by race/ethnicity and geographic region. Despite the increase in oocyte cryopreservation, return for oocyte warming over a 5-7-year follow-up period was low, with a significant portion of cryopreserved oocytes remaining unused. Patients who were older at time of oocyte cryopreservation were more likely to return and had a shorter interval between oocyte cryopreservation and warming. Though rates of oocyte warming are low, the outcomes for patients who do return to utilize cryopreserved oocytes are reassuring. Most patients have a usable embryo after oocyte warming and the live birth rates are reassuring and demonstrate an expected age-related decline. However, given the low return rate, the yield on a per-planned oocyte cryopreservation cycle is very low.
Lee et al. (Fri,) studied this question.