The fetal membranes consist of the chorion, amnion, yolk sac, and allantois. The chorion has three layers: cytotrophoblastic, chorionic connective tissue, and basement membrane. The chorion lies ...

This finding suggested that the human placenta has another progenitor niche. Here we show that the chorion is one such site. Initially, we immunolocalized pluripotency factors and trophoblast fate ...