Stages of embryonic rotation of the gut

Between the 5th and 10th week of gestation, the midgut loop elongates by herniating out into the umbilical cord. The midgut communicates with the yolk sac by the vitellointestinal duct (Vitellius duct).

First midgut rotates by 90° counterclockwise around the superior mesenteric artery. Then it re-enters in the abdominal cavity undergoing another 180° counterclockwise rotation.

After complex 270° counterclockwise rotation (90°+180°), the cecum is in the right upper quadrant of the abdominal cavity. Thereafter enlargement of the colon pushes the cecum down into its final position.