The human embryo following biopsy on day 5 versus day 3: viability, ultrastructure and spindle/chromosome configurations.

Research Question: Are there any differences in viability, spindle abnormalities and mitochondrial and other organelle structures amongst embryos biopsied on day 3 versus day 5 before and after vitrification?

Design: A total of 240 day 3 biopsied embryos that developed to blastocysts but were rejected for transfer following preimplantation genetic testing for monogenic/single gene defects (PGT-M) (n = 115) or for aneuploidies (PGT-A) (n = 125) were divided into two groups: (i) 120 blastocysts treated for viability, spindle/chromosome configuration (SCC) analysis and transmission electron microscopy (TEM) analysis (fresh n = 20, n = 20, n = 20 and following vitrification/warming n = 20, n = 20, n = 20); (ii) 120 embryos were re-biopsied at the blastocyst stage and treated for viability, SCC and TEM analysis (fresh n = 20, n = 20, n = 20 and following vitrification/warming n = 20, n = 20, n = 20). Also, 60 vitrified blastocysts biopsied only on day 5 that were rejected for transfer following PGT-M (n = 6) or PGT-A (n = 54) were treated following warming for viability (n = 20), SCC (n = 20) and TEM analysis (n = 20).

Results: No differences were observed in SCC and ultrastructure between embryos biopsied on day 5 and day 3 but following vitrification higher numbers of abnormal spindles, distension of mitochondria, multivesicular bodies, lipofuscin droplets, altered cell junctions and occasionally excessive accumulation of glycogen granules were evident.

Viability assessment using fluorescent markers and ultrastructure of human biopsied embryos vitrified in open and closed systems.

Research Question: Are there any differences in viability and ultrastructure amongst embryos biopsied on Day 5 versus Day 3 following vitrification in open and closed systems and compared to fresh embryos?

Design: One hundred human embryos (40 blastocysts biopsied on Day 5 and subsequently vitrified in open or closed systems and 60 Day 3 biopsied embryos that developed to blastocysts but were rejected for transfer following preimplantation genetic testing for monogenic/single gene defects and for aneuploidies were either treated fresh [n = 20] or vitrified [n = 40] in open or closed systems) and following warming and culture for 4 h were subjected to viability staining with carboxyfluorescein-diacetate succinimidylester/propidium iodide or processed for transmission electron microscopy.

Results: No statistically significant differences were observed in the viability of human biopsied embryos following vitrification in open and closed systems. Compared to fresh embryos, vitrified ones had a higher incidence of damage (propidium iodide-stained cells) irrespective of the vitrification method (P = 0.

Day-5 fresh embryo transfer is associated with superior clinical outcomes in oocyte donation cycles compared with day-3 embryo transfer.

Objective: Τo compare clinical outcomes between day-5 (D5ET) and day-3 (D3ET) fresh embryo transfer in oocyte donation cycles.

Study Design: A retrospective analysis of prospectively collected cohort data was performed enrolling all participants in an oocyte donation program performed either D5ET or D3ET regarding the period from June 2006 to June 2018. Cycles were compared by the day of embryo transfer.

Closed vs. Open Oocyte Vitrification Methods Are Equally Effective for Blastocyst Embryo Transfers: Prospective Study from a Sibling Oocyte Donation Program.

Purpose: To assess whether open and closed vitrification protocols are equally effective for sibling-oocyte cycles when performing blastocyst embryo transfers.

Materials And Methods: A prospective study was set up comparing the open and the closed vitrification techniques in oocyte recipients sharing sibling oocytes between 2014 and 2016. Sibling oocytes were randomly and equally assigned into the closed group (oocytes vitrified in a closed system) or the open group (oocytes vitrified in an open system).

Spindle and chromosome configuration analysis of human biopsied versus non-biopsied embryos by confocal laser scanning microscopy following vitrification.

SummaryThe aim of this study was to investigate the effects of zona drilling and biopsy on day 3 followed by vitrification on day 5 on the cytoskeleton and development of human embryos, by analysing survival rates and spindle and chromosome configurations by fluorescence and confocal laser scanning microscopy in human biopsied and non-biopsied embryos. In total, 98 human blastocysts (50 non-biopsied and 48 following biopsy on day 3) were vitrified on day 5 using either a commercial dimethyl sulphoxide (DMSO)-free vitrification kit or increasing concentrations of DMSO/EG (5%/5-10%/10-20%/20%). Following warming, the blastocysts were allowed to recover in culture for 24 h and were immunostained with α-tubulin, acetylated tubulin, and/or γ-tubulin antibodies in combination with 4',6-diamidino-2-phenylindole (DAPI).