Storage trends, usage and disposition outcomes following egg freezing

Research question: What happens to eggs after egg freezing? Design: A retrospective cohort study was performed spanning 2012–2022. Data were obtained from seven assisted reproductive technology clinics in Victoria, Australia. Aggregated, de-identified data were collected on cycles that resulted in egg freezing and the following outcomes, including treatment involving thawed eggs and disposition outcomes of surplus eggs. Results: The number of patients with eggs in storage grew rapidly from 144 in 2012 to 2015 in 2022. In 2022, 73% of patients had stored their eggs for <5 years, 25% for 5–10 years, and 2% for ≥10 years. Most thaw cycles (600/645, 93%) involved eggs that had been frozen for <5 years, of which 47% had been frozen for <6 months. Overall, the live birth rate per initiated thaw cycle was 12%. Across the study period, 2800 eggs from 286 patients were either discarded, donated or exported. Of the 128 patients who discarded their eggs, 32% had stored their eggs for <5 years, 32% for 5–10 years and 36% for >10 years. Of the 23 patients who donated their eggs to someone else, all but four had stored their eggs for <5 years. No eggs were donated to research over the study period. Conclusions: This study shows that very few patients have made the decision to use or relinquish their eggs. Strategies may be needed to address the prolonged storage of surplus eggs, and ensure that patients are supported to make decisions regarding the fate of their eggs which align with their preferences and values.