RESUMO
Purpose: This study aimed to evaluate the effects of swim-up and density gradient centrifugation methods on sperm DNA fragmentation. Methods: Nineteen normozoospermic patient samples with ≥100 × 106 motile sperms were included in this study. Sperm DNA fragmentation, progressive motility, and progressive motile sperm number were measured before and after the swim-up method or density gradient centrifugation. Results: Sperm DNA fragmentation was not statistically different between swim-up-(14.4 ± 2.1%, p = 0.32) and density gradient centrifugation-processed (25.0 ± 3.0%, p = 0.20) and unprocessed semen samples (19.2 ± 1.9%). Sperm DNA fragmentation was significantly lower in swim-up-than in density gradient centrifugation-processed samples (p < 0.05). Sperm progressive motility was significantly higher (p < 0.05) in swim-up-(92.9 ± 1.0%) and density gradient centrifugation-processed (81.3 ± 2.0%) samples, with the former being higher, than in unprocessed semen samples (53.1 ± 3.7%). The recovery rate of progressive motile sperms was significantly lower in swim-up-(9.7 ± 1.4%) than in density gradient centrifugation-processed samples (17.2 ± 1.8%, p < 0.05). Conclusions: The swim-up method is superior to density gradient centrifugation, evidenced by less sperm DNA fragmentation and higher sperm progressive motility. The recovery rate of progressive motile sperms was better after density gradient centrifugation than after swim-up.
RESUMO
BACKGROUND: The failure of frozen-thawed blastocysts to re-expand adequately within a few hours after warming has been reported to have a negative impact on assisted reproductive technology (ART) outcomes. However, the extent to which this failure truly affects ART outcomes has not yet been presented in a manner that is easily understandable to medical practitioners and patients. This study aimed to assess the effects of blastocyst shrinkage on ART outcomes and determine a more effective morphological evaluation approach for use in clinical settings. METHODS: This retrospective observational cohort study of frozen-thawed blastocyst transfer cycles was conducted from April 2017 to March 2022. Overall, 1,331 cycles were eligible for inclusion, of which 999 were good-quality blastocysts (GQB) and 332 were non-good-quality blastocysts (non-GQB). All frozen-thawed blastocyst transfer cycles performed during the specified study period were included in the study. Exclusion criteria were established to mitigate potential sources of bias as these cycles could impact implantations. We calculated rates and age-adjusted odds ratios of implantation, clinical pregnancy, ongoing pregnancy, and live birth of the re-expansion group, which showed sufficient expansion, and shrinkage group, which showed insufficient expansion. We also calculated the implantation, clinical pregnancy, ongoing pregnancy, and live birth rates of the re-expansion and shrinkage groups for each morphological scoring system parameter. RESULTS: A reduced ART outcome was observed with use of blastocysts with shrinkage after vitrification/warming. The age-adjusted odds ratios for implantation, clinical pregnancy, ongoing pregnancy, and live birth were lower in the shrinkage group than in the re-expansion group. CONCLUSIONS: This study examined the adverse effect of blastocyst shrinkage after warming and recovery culturing on reproductive outcomes in a clinically useful manner by retrospectively examining a substantial number of frozen-thawed embryo transfer cycles. The study findings can possibly reduce concerns regarding over- or under-estimation of blastocyst implantation by allowing providers and patients to refer to the data.
