Carnegie stages

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The Carnegie stages or embryonic stages are a division of human embryonic development into 23 stages during the eight weeks of the embryonic period from fertilization to the beginning of the fetal period .

The staging was developed in 1942 by George Linius Streeter (1873-1948), an American embryologist , at the Carnegie Institution for Science in Baltimore . Then an embryo is assigned to the various stages according to its morphological characteristics. He originally called these stages horizons . He and his colleagues gained their knowledge from rhesus monkey embryos, since early human embryos were not available.

In 1987 the classification was completed by Ronan R. O'Rahilly and Fabiola Müller of the University of California and the stages are now referred to as embryonic or Carnegie stages.

The post-development staging allows a more precise classification than would be possible by size or age, although the ratio between the stages and the embryo size is fairly constant.

literature

  • Ulrich Drews: Pocket Atlas of Embryology . Georg Thieme Verlag, Stuttgart 2006, ISBN 3-13-109902-X , p. 40 ( full text in Google Book Search).

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