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Updated: Dec 29, 2025

Human Blastocyst Biopsy and Vitrification
Published on: July 26, 2019
Blastulation of a zygote to a hatched blastocyst without any clear cell division: an observational finding in a
N L Sandi-Monroy1,2, S Musanovic3,4, D Zhu3,4
1IVF Laboratory, Kinderwunsch-MVZ Ulm GmbH, Einsteinstrasse 59, 89077, Ulm, Germany. sandi-monroy@kwz-ulm.de.
Purpose:
To describe an interesting not previously described morphokinetic finding.
Methods:
Retrospective case report of a couple undergoing controlled ovarian stimulation (COS) followed by in vitro fertilization and blastocyst transfer.
Results:
We identified a unique finding of blastulation of a fertilized human zygote after conventional in vitro fertilization. The fertilized zygote did not show any clear cytokinesis until approximately 107 h post insemination, when it started dividing into a blastocyst. By 113 h post insemination, inner cell mass and trophectoderm cells could be clearly distinguished and the blastocyst was completely hatched by 136 h post insemination.
Conclusion:
Time-lapse systems offer more detailed observations of embryonic development. Here, we report an atypical development of an embryo that was not described previously. We hope to become an insightful discussion among peers and incentive the publication of such findings in the future.
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