Fig. 1

The interface between intervillous space and uterine tissue: myometrial side. a Bundles of muscle fibres in myometrium are lined by an endothelial layer (CD31 staining; red). b The layer around the bundles of muscle fibers in myometrium is not cytokeratin-positive (cytokeratin staining; green). IVS = Intervillous space, myo = Myometrium