The hatching of a blastocyst where the blastocyst portions on the inside and the outside of the zona pellucida feature a figure-of-eight shape is termed "8"-shaped hatching; this type of hatching has been reported to affect the proper presentation of the inner cell mass (ICM) in both human and mouse embryos. Here, our aim was to investigate the factors that affect ICM presentation during "8"-sh...

Biological functions of hyaluronan (HA) depend on its molecular size. Small size HAs are known to regulate cell proliferation; however, the expression of HA synthases (HASs) and hyaluronidase-2 (HYAL2) and their role during early embryo development have not been previously identified. In this paper, we have shown by immunostaining that HA is produced by bovine in vitro-produced embryos at all s...

The objective was to determine cryotolerance of in vitro cultured rabbit embryos to the open-pulled straw (OPS) method. Overall, 844 rabbit embryos at pronuclear, 2- to 4-cell, 8-cell, and morula/blastocyst stages were vitrified, and ≥ 1 mo later, were sequentially warmed, rehydrated, and subjected to continuous culture (n = 691) or embryo transfer (ET, n = 153). Embryos vitrified at the 8-cell...

This study assesses the fertilization and blastocyst-forming rate in mice cumulus-oocyte complexes (COCs) after the exposure of human ovarian endometriotic fluid. Endometriotic fluid was obtained from a single patient by aspiration at the time of a laparoscopic cystectomy and serially diluted. COCs were obtained from 46-week-old female BDF1 mice. After exposure to ovarian endometriotic fluid fo...

The aim of the present study was to clarify the efficacy of the well of the well (WOW) culture system for a small number of embryos and the effect of number of adjacent embryos in a WOW dish on blastocyst development. In conventional droplet culture, embryos in the small-number group (5-6 embryos/droplet) showed low blastocyst development compared with a control group (25-26 embryos/droplet). H...

The antioxidant effect of N, N-dimethylglycine (DMG) on in vitro-produced (IVP) bovine embryos was examined. After in vitro fertilization, presumptive zygotes were cultured with or without 0.1 μM DMG under different oxygen tensions. The percentage of embryos developing to the blastocyst stage was lowest under a 20% oxygen concentration without DMG, and it was significantly increased (P < 0.05) ...

The use of sequential media has made extended culture and transfer of blastocysts feasible for human IVF. Embryo transfer on day 5 has been claimed to result in higher implantation rates than transfer on day 3, on the basis of retrospective comparative studies. This is not supported convincingly, however, in randomized controlled trials published to date. Blastocyst culture imposes additional r...

The mechanisms controlling the establishment of the embryonic-abembryonic (E-Ab) axis of the mammalian blastocyst are controversial. We used in vitro time-lapse imaging and in vivo lineage labeling to provide evidence that the E-Ab axis of the mouse blastocyst is generated independently of early cell lineage. Rather, both the boundary between two-cell blastomeres and the E-Ab axis of the blasto...

background: the values of embryonic stem cell and cloning are evident. production of clone from embryonic stem cells can be achieved by introduction of stem cell into a tetraploid blastocyst. tetraploid blastocyst can be produced in vitro by electrofusion of 2-cell embryos. objective: the aim of this study was to assess the effect of different voltages and durations on fusion rate of bovine 2-c...

Background Embryo morphology has been proposed as an alternative marker of chromosomal status. The objective of this retrospective cohort study was to investigate the association between the chromosomal status on day 3 of embryo development and blastocyst morphology.Embryo morphology has been proposed as an alternative marker of chromosomal status. The objective of this retrospective cohort stu...