Abstract
PURPOSE: To investigate whether re-biopsy and re-vitrification affect embryo developmental potential and clinical outcomes. METHODS: Embryos that underwent preimplantation genetic testing for aneuploidy (PGT-A) and single embryo transfer between December 2017 and April 2024 were studied. All embryos were categorized into three groups: fresh biopsy and vitrification (BV group; n = 346); thawed, biopsied, and subsequently vitrified (VBV group; n = 12); fresh biopsied, vitrified, further thawed and biopsied again due to inconclusive results from the previous biopsy (BVBV group; n = 19). The live birth rate and miscarriage rate will be evaluated after embryo transfer in each group. RESULTS: Live birth rate (LBR) was not statistically significant among the BV group (50.00%), VBV group [41.67%; adjusted relative risks (aRR) 0.96; 95% confidence interval (95% CI): 0.81-1.14], and BVBV group (42.11%; aRR 0.97, 95% CI: 0.83-1.13). The miscarriage rate was not statistically significant: BV group (11.27%); VBV group (25%; aRR 1.09, 95% CI: 0.95-1.25), and BVBV group (5.26%; aRR 0.97, 95% CI: 0.91-1.02). CONCLUSIONS: The differences in LBR and miscarriage rates among the groups were not statistically significant. However, the limited sample sizes of the VBV and BVBV groups cannot rule out the possibility of moderate differences. Some embryos can be successfully salvaged, leading to live births. To minimize inconclusive results, the laboratory should refine the procedural details.