The Visible Embryo is a visual guide through fetal development from fertilization through pregnancy to birth. As the most profound physiologic changes occur in the “first trimester” of pregnancy, these Carnegie stages are given prominence on the birth spiral.
The shape and location of embryonic interal structures and how they relate and are connected to each other is essential to understanding human development. Medical professionals create a mental picture of this process in order to determine how well the fetus is progressing. It is also the basis of knowing how and when errors in development occur and if a possibility exists for a corrective intervention.
It is equally important for expectant parents to understand the relationship of these internal structures and how their infant develops through pregnancy.
Creating the images for The Visible Embryo, included capturing data from slides and three dimensional structures on fetal anatomy in The National Institutes of Health, Carnegie Collection of embryos, as well as from 3D and 4D ultra sound images.
A very nice graphic resource.