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Carnegie Stage   Figure

Trophoblast herniation

Trophoblast herniation

Close-up view of a stage 3 embryo in vitro showing trophoblast herniation that is the beginning of the hatching process. The trophoblast begins to herniate through a small opening in the zona pellucida. The blastocyst is fully expanded and surrounded by a thin zona pellucida.

From: Veeck and Zaninovic´, 2003. Reproduced with permission of the publisher, Francis and Taylor Group.


Keywords: blastocyst(s), blastocystic cavity (blastocoele), expanded blastocyst, thin zona pellucida, trophoblast, trophoblast herniation, zona pellucida


Source: The Virtual Human Embryo.