7h 25min, feb 22, 2002 y - Weeks 3 The cavity will soon be the yolk sac, delivering nutrients to the embryo. The egg is now a "blastocyst" burrowing into the blood-rich uterine lining.
Description:
https://www.babycenter.com/6_your-pregnancy-3-weeks_1049.bcAdded to timeline:
Date:
7h 25min, feb 22, 2002 y
Now
~ 23 years ago