What is the projection of the umbilical cord considered in embryology?

• A. Umbilical herniation
• B. Physiologic herniation
• C. Pathologic herniation
• D. Normal protrusion

Answer: (B)

During early development, the midgut grows quickly and temporarily protrudes into the umbilical cord. This normal, transient event is called physiologic herniation. It starts around the sixth week and the intestines return to the abdominal cavity by about the tenth week, with rotation occurring as they re-enter. This distinguishes it from pathologic protrusions, which are due to defects in the abdominal wall and do not resolve as part of normal development. So the correct concept is physiologic herniation—the normal, temporary projection of the gut into the umbilical cord during early embryogenesis.