Thomas Ebner1, Alexandra Höggerl2, Peter Oppelt3, Elisabeth Radler3, Simon-Hermann Enzelsberger3, Richard B Mayer3, Erwin Petek2, Omar Shebl3. 1. Department of Gynecology, Obstetrics and Gynecological Endocrinology, Kepler University Clinic, Campus IV, Krankenhausstr. 26-30, 4020, Linz, Upper Austria, Austria. thomas.ebner@gespag.at. 2. Institute of Human Genetics, Medical University of Graz, Graz, Styria, Austria. 3. Department of Gynecology, Obstetrics and Gynecological Endocrinology, Kepler University Clinic, Campus IV, Krankenhausstr. 26-30, 4020, Linz, Upper Austria, Austria.
Abstract
PURPOSE: Recently, guidelines on the annotation of dynamic human embryo monitoring recommended screening for the presence of planar blastomere arrangement at the 4-cell stage. This observational study was set up in order to analyze whether developmental kinetics of planar human embryos are different from tetrahedral ones. METHODS: Therefore, embryos of 115 consecutive ICSI patients (showing 32 planar and 554 tetrahedral embryos) were cultured in a new time-lapse system (Miri TL) and their embryos were annotated for morphokinetic development and screened for irregular cleavages and morphological dysmorphisms. RESULTS: Significantly less planar embryos reached blastocyst stage and showed worse quality as compared to regular tetrahedral embryos. The rate of bi- and/or multinucleation was also significantly higher in the affected group. Irregular cleavages, particularly embryo rolling, were more often seen in planar embryos. Morphokinetics between planar and tetrahedral were distinguishable up to 4-cell stage (t2-t4), thereafter the observed delay in planar embryos (t8) was more likely the result of a higher rate of arrested embryos in the planar group. CONCLUSIONS: Planar embryos are associated with both a significant increase in irregular cleavage as well as a delay in preimplantation development. This indicates that planar embryos are rather abnormal and should only be considered for transfer if no other embryos are available.
PURPOSE: Recently, guidelines on the annotation of dynamic human embryo monitoring recommended screening for the presence of planar blastomere arrangement at the 4-cell stage. This observational study was set up in order to analyze whether developmental kinetics of planar human embryos are different from tetrahedral ones. METHODS: Therefore, embryos of 115 consecutive ICSI patients (showing 32 planar and 554 tetrahedral embryos) were cultured in a new time-lapse system (Miri TL) and their embryos were annotated for morphokinetic development and screened for irregular cleavages and morphological dysmorphisms. RESULTS: Significantly less planar embryos reached blastocyst stage and showed worse quality as compared to regular tetrahedral embryos. The rate of bi- and/or multinucleation was also significantly higher in the affected group. Irregular cleavages, particularly embryo rolling, were more often seen in planar embryos. Morphokinetics between planar and tetrahedral were distinguishable up to 4-cell stage (t2-t4), thereafter the observed delay in planar embryos (t8) was more likely the result of a higher rate of arrested embryos in the planar group. CONCLUSIONS: Planar embryos are associated with both a significant increase in irregular cleavage as well as a delay in preimplantation development. This indicates that planar embryos are rather abnormal and should only be considered for transfer if no other embryos are available.
Authors: Omar Shebl; Philip Sebastian Trautner; Sabine Enengl; Elisabeth Reiter; Christina Allerstorfer; Tamara Rechberger; Peter Oppelt; Thomas Ebner Journal: J Assist Reprod Genet Date: 2021-10-13 Impact factor: 3.412