Search

The objective of this prospective cohort study was to investigate whether cryopreservation of cleavage or blastocyst stage embryos improves in vitro fertilization outcomes in recurrent implantation failure (RIF) patients. The study comprised 575 patients who were allocated to receive either single frozen/thawed blastocyst-stage transfer (SBT) or frozen/thawed double-cleavage-stage embryo transfer (DET). The clinical pregnancy rate, implantation rate, and ongoing pregnancy rate were higher in the SBT group compared with the DET group (41.15% vs. 27.11%, p < 0.001; 41.15% vs. 19.28%, p < 0.001; 40.03% vs. 25.9%, p < 0.001), but the miscarriage rate did not differ between the two groups. It was concluded that frozen/thawed SBT could be a preferred strategy for RIF patients. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the incidence of oocytes with severe ovoid zona pellucida (ZP), investigate the development potential of their sibling oocytes and the clinical outcomes from affected cycles. The data were collected from our medical records. Cycles having at least one oocyte with severe ovoid ZP were defined as the ‘severe ovoid group’, cycles having at least one oocyte with mild ovoid ZP were defined as the ‘mild ovoid group’, whereas cycles without oocytes with ovoid ZPs were defined as the ‘control group’ (n = 150 for each group). The results showed that sibling embryos in the ‘severe ovoid group’ were characterized by delayed development and lower available embryo rate. The implantation, clinical pregnancy and live birth rates in this group were also significantly lower than that in the other two groups. There were five cycles in which only one embryo with severe ovoid ZP was transferred and two healthy babies were born. The mild ovoid group showed comparable embryo development and clinical outcomes compared with the control group. This study suggests that cycles containing oocytes with severe ovoid ZPs had delayed embryo development, lower available embryo rate, compromised implantation, clinical pregnancy and live birth rates. [ABSTRACT FROM AUTHOR]

Is the total duration of spontaneous blastocyst collapse to re-expansion before biopsy related to ploidy and live birth rates after single euploid blastocyst transfer? This was a retrospective cohort study of 600 preimplantation genetic testing cycles for aneuploidy (PGT-A) cycles, involving 2203 biopsied blastocysts, at a large reproductive medicine centre. Features of spontaneous blastocyst collapse from full to expanded stage, before biopsy, were observed using an embryoscope viewer for embryos cultured in a time-lapse incubator. In total, 568 cycles of frozen blastocyst transfers, either single euploid or mosaic, were performed. Correlations between collapse features and PGT-A outcomes were evaluated, as well as live birth rate, following euploid embryo transfer. Blastocysts with lower morphological quality or delayed development had significantly higher rates of collapse, multiple collapses, and a longer duration of collapse to re-expansion. After controlling for confounders, such as oocyte age, morphological quality of blastocyst, and day of biopsy, multivariate logistic regression revealed that the total duration of collapse to re-expansion was an independent predictor of lower euploidy rate; the multivariate OR was 0.85 (95% CI 0.77–0.95; P = 0.00). Furthermore, even with euploid embryo transfer, the probability of a live birth decreased as the total duration of collapse to re-expansion increased; the multivariate OR was 0.79 (95% CI 0.64–0.98; P = 0.033). The total duration of blastocyst collapse to re-expansion could be used as a predictor of lower euploidy and live birth rate. When developing blastocyst algorithms for pregnancy prediction, the duration of spontaneous blastocyst collapse should be included as a significant variable. [ABSTRACT FROM AUTHOR]