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The Endowment for Human Development
The Endowment for Human Development
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Hatching Blastocyst

5 days

Hatching Blastocyst [Click for next image]
Source: Centro Riproduzione Assistita, Catania, Italy.

Note:

The embryo needs space and it needs to implant in the wall of the uterus if it is to survive. The zona must go!

Note:

Hatching is a phenomenon seen with embryos developing outside the body. Under natural conditions inside the body, the zona is believed to degenerate and disappear after the embryo reaches the uterine cavity and prepares to implant.

Label Key:

1. zona pellucida
2. embryo escaping from the zona (called hatching)
3. blastocyst cavity
4. perivitelline space
All ages referenced to fertilization, not last menstrual period.
Blastocyst
Blastocyst
Blastocyst with Inner Cell Mass
Blastocyst with Inner Cell Mass
Hatching Blastocyst
Hatching Blastocyst
Hatching Blastocyst
Hatching Blastocyst
Hatched Blastocyst
Hatched Blastocyst
Hatched Blastocyst
Hatched Blastocyst
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