title: Time-lapse cleavage rating predicts human embryo viability.
abstract: Chronology of three consecutive mitotic events in human pre-implantation embryos was examined by time-lapse imaging. In zygotes producing well-formed and pregnancy-yielding expanded blastocysts, uniform time-patterning of cleavage clusters (c) and interphases (i) was revealed: i2=11+/-1, i3=15+/-1, i4=23+/-1 h / c2=15+/-5, c3=40+/-10, c4=55+/-15 min. Oppositely, shortened or prolonged durations of one or more cell cycles were strongly predictive of poor implantation and development. Furthermore, trichotomic mitosis was discovered in 17 % of cases - zygotes cleaved into 3 blastomeres and 2-cell embryos into 5-6 cells (instead of normal 2 and 4). During conventional clinical assessment, such embryos are indistinguishable from normal, often considered just-in-course of the next cell cycle. Only detailed time-lapse monitoring paced at 10-minute intervals had proven all these embryos to be absolutely unviable, even in rare cases when they reduced their hypercellularity to normal cell counts via cell-cell fusion. Overall, we demonstrate that time-lapse embryo cleavage rating (ECR) as a standalone diagnostic procedure allows for effective identification of viable early embryos with 90 % specificity, while elimination of good-looking but unviable embryos can be assumed with a specificity of 100 %. Thus, making this non-invasive and contactless approach worth of addition to routine embryo screening in clinical IVF programs.
authors.affiliation: Fetal Medicine Program, Department of Cell Biology, Šafárik University, Košice, Slovak Republic.
authors.forename: D
authors.initials: D
authors.lastname: Hlinka
authors.forename: B
authors.initials: B
authors.lastname: Kaľatová
authors.forename: I
authors.initials: I
authors.lastname: Uhrinová
authors.forename: S
authors.initials: S
authors.lastname: Dolinská
authors.forename: J
authors.initials: J
authors.lastname: Rutarová
authors.forename: J
authors.initials: J
authors.lastname: Rezáčová
authors.forename: S
authors.initials: S
authors.lastname: Lazarovská
authors.forename: M
authors.initials: M
authors.lastname: Dudáš
mesh_terms: D001755:Blastocyst / Q000166:cytology*; D002970:Cleavage Stage, Ovum / Q000166:cytology*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D011247:Pregnancy; D019836:Preimplantation Diagnosis / Q000379:methods*; D059008:Time-Lapse Imaging / Q000379:methods*