Carnegie Stage 20 Definition

Age is approximately 50-51 postovulatory days

Length is approximately 21-23mm

External Features Include: the upper limbs have become slightly bent at the elbows; hands have short, stubby fingers and are still far apart, a delicate fringe-like vascular plexus appears in the superficial tissue of the head and the edge of the plexus is approximately halfway between ear-eye level and the vertex of the head.

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