This review examines the strengths and weaknesses of animal models of human
placentation and pays particular attention to the mouse and non-human primates. Analogies
can be drawn between mouse and human in placental cell types and genes controlling
placental development. There are, however, substantive differences, including a different
mode of implantation, a prominent yolk sac placenta, and fewer placental hormones in the
mouse. Crucially, trophoblast invasion is very limited in the mouse and transformation of …