健康・医療情報学ジャーナル

Human Embryonic Behavior Observed with Time-Lapse Cinematography

Abstract

Yasuyuki Mio*,Kyoko Iwata,Keitaro Yumoto,Kazuo Maeda

To clarify developmental behavior in human embryos, we observed oocytes with in vitro fertilization and intracytoplasmic sperm injection and donated embryos up to 5 days using our original time-lapse cinematography (TLC) system. The TLC analyses demonstrated several novel aspects and events that were not visible by intermittent stillframe microscopy. Here, we present the entire fertilization process in which we founded the fertilization cone, cytoplasmic flare, dynamic change of nuclear precursor body and cytoplasmic halo. We also demonstrated the occurrence of zygotes with a single pronucleus (PN) and uneven 2PN, fragmentation, blastocoel collapse during the blastocyst stage, and the hatching pattern of expanded blastocysts. Observing such morphokineses in human embryos will enhance our understanding of human embryonic behavior up to preimplantation.