Carnegie Stage 23 Definition

Age is approximately 56 postovulatory days

Length is approximately 28-30mm (middle range); full range is 23-32mm

External Features Include: The eyelids are starting to fuse at margins. The superficial vascular plexus is rapidly approaching the vertex of the head. The limbs have increased markedly in length and show more advanced differentiation of their subdivisions.

(O'Rahilly R and Muller F [1987] Developmental Stages in Human Embryos. Carnegie Institute, Washington, Publication no. 637)