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Carnegie Stages

Carnegie stages are a series of 23 developmental stages used to describe the human embryonic period, which is the first 8 weeks of development before the term "fetus" is used. The stages are mainly based on external features, rather than size, and take their name from the human embryo collection at the Carnegie Institution of Washington. For more information about the stages, please see our staging criteria.

    A 3D model of a human embryo, Carnegie stage 11   A 3D model of a human embryo, Carnegie stage 12   A 3D model of a human embryo, Carnegie stage 13
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A 3D model of a human embryo, Carnegie stage 14   A 3D model of a human embryo, Carnegie stage 15   A 3D model of a human embryo, Carnegie stage 16   A 3D model of a human embryo, Carnegie stage 17   A 3D model of a human embryo, Carnegie stage 18
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A 3D model of a human embryo, Carnegie stage 19   A 3D model of a human embryo, Carnegie stage 20   A 3D model of a human embryo, Carnegie stage 21   A 3D model of a human embryo, Carnegie stage 22   A 3D model of a human embryo, Carnegie stage 23
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