After the fertilization the egg, now named embryo ( = a fertilized egg) will take its journey down the tubes and enter the uterine cavity 4 days later. At this time the embryo has cleaved and comprises more than 100 cells. At day 6 after fertilization, the embryo, now called the blastocyst, will be implanted into the uterine wall.

This process is illustrated in the figure kindly provided by Ferring

Illustration kindly provided by Ferring

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