Background: In spite of the great advances in vitrification, the mechanism of embryo damage which occure in some cases and varies from one case to another case is not exactly understood. Since Zona pellucida has an important role on early embryonic development, the aim of the present study is to investigate the effect of vitrification on integrity of zona pellucida and surveillance of blastocys...

BACKGROUND Human embryos produced by in vitro fertilization (IVF) are usually cultured to day 6 after insemination, and good quality of embryos should develop to blastocyst stage at days 5 and 6. However, some embryos develop slowly, thus they may form blastocysts on day 7. Most IVF laboratories culture embryos to day 6 and then discard retarded embryos that do not develop to blastocyst stage. ...

OBJECTIVE To assess the effect of implementing different previtrification interventions on the postwarming DNA integrity of vitrified blastocysts. DESIGN Prospective in vitro study. SETTING Center for Reproductive Medicine laboratory in a tertiary hospital setting. ANIMALS A total of 70 expanded and 46 nonexpanded mouse blastocysts were used for the study. INTERVENTION(S) [1] Twenty-two...

In this study, the effect of heat shock on frozen-thawed blastocysts was evaluated using in vitro-produced (IVP) bovine embryos. In experiment 1, the effects of 6 h of heat shock at 41.0 C on fresh blastocysts were evaluated. HSPA1A expression as a reflection of stress was increased by heat shock (P < 0.05), but the expressions of the quality markers IFNT and POU5F1 were not affected. In experi...

The objective was to determine whether the hatching stage of cattle and swamp buffalo somatic cell nuclear-transferred (SCNT) blastocysts affected cryosurvival after vitrification, and whether addition of linoleic acid-albumin (LAA) to the IVC medium and Ficoll to the vitrification solution improves cryosurvival. Fused couplets were activated with ethanol and cycloheximide-cytochalasin D (day 0...

The role of actin filaments and contractions in hatching was determined in mouse blastocysts whose actin filament bundling abilities had been suppressed by H-89, an inhibitor of protein kinase A. The hatching rate of blastocysts developed from morulae in a medium containing H-89 at a concentration of 4.0 microM was 17.2%, which was significantly lower than the 76.7% of the control blastocysts d...

The occurrence of apoptosis in a fraction of blastomeres in the preimplantation embryo is well known but the consequences of this phenomenon for the developmental potential of the blastocyst has not been well established. Here we demonstrate that blastocysts with low amounts of activated group II caspase activity have increased potential for development to the hatched blastocyst stage. Bovine b...

OBJECTIVE Under estrogen deficiency, blastocysts cannot initiate implantation and enter dormancy. Dormant blastocysts live longer in utero than normal blastocysts, and autophagy has been suggested as a mechanism underlying the sustained survival of dormant blastocysts during delayed implantation. Autophagy is a cellular degradation pathway and a central component of the integrated stress respon...

BACKGROUND To optimize blastocyst cryopreservation, the prerequisite is to develop a better understanding of factors that influence their survival and implantation potential. Therefore, the aim of the present work was to evaluate, retrospectively, the outcome of blastocyst cryopreservation in a day 2/3 fresh embryo transfer programme. METHODS Two different freezing strategies were compared: a...

BACKGROUND Fresh embryo transfer results in higher live birth rates, while thawed embryo transfer appears to result in healthier babies. This study aims to investigate the association between the transfer of fresh or thawed embryos at the cleavage or blastocyst stage and the perinatal outcomes. METHODS This analysis is a retrospective population-based study of 150 376 autologous embryo transf...