In this illustration, the semi-transparent outer layer of the embryo shows the mound of cells, called the embryoblast, on the inside. The uterine wall can be seen under the embryo, and it’s here that implantation will happen.
![](https://assets.oviahealth.com/wp-content/uploads/2023/12/article_109190_week-4_s_640_533.jpg)
In this illustration, the semi-transparent outer layer of the embryo shows the mound of cells, called the embryoblast, on the inside. The uterine wall can be seen under the embryo, and it’s here that implantation will happen.