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The Endowment for Human Development
The Endowment for Human Development
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Slideshow: Early Events

Free Blastocyst (without zona)

#57, Slide 22 of 24

6 days

Source: Centro Riproduzione Assistita, Catania, Italy.

Note:

This close-up reveals the absence of the zona and the large size of the blastocyst cavity. The inner cell mass is tiny by comparison.

Label Key:

1. inner cell mass
2. blastocyst cavity
All ages referenced to fertilization, not last menstrual period.
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