[The microtexture of amnion and chorion connective tissue].

On microscopical, stereo-scan and TEM observations the microtexture of the connective tissue of amnion and chorion have been analysed. The "compact layer" of the amnion-connective tissue consists of single collagen fibrils, which are arranged felt-like in parallel layers. In the "fibroblast layer" the fibrils are mostly arranged in bundles, forming a network. Single fibrils and bundles of fibrils in both layers are arranged surface parallel. The superficial layer of the chorion's connective tissue is predominated by wave-like bundles of fibrils in parallel and latticed arrangements, which are consolidated by transversely and diagonally running fibres. In the inferior layer the fibres leave their formation, run diagonally in the direction of the trophoblast and interweave with each other to a mat of fibrils at the border to the trophoblast. The tensile strength of the amnion connective tissue is due to the felt-like fibril texture of the "compact-layer" and the special arrangement of surface-parallel collagen fibres and fibrils.