Topic Completed: 1 October 2011

Revised: 28 August 2019

Copyright: (c) 2003-2019,, Inc.

PubMed search: Embryology[TIAB] esophagus

Poonam Sharma, M.D.
Page views in 2019: 227
Page views in 2020 to date: 57
Cite this page: Sharma P. Embryology. website. Accessed March 31st, 2020.
Definition / general
  • Notocord induces formation of foregut from endoderm
  • At day 21 (end of week 3), lateral walls of foregut develop septa that fuse and divide foregut into esophagus and trachea
  • At week 4, myenteric plexus develops
  • At weeks 5 - 6, septation of walls ends; initial lining is stratified columnar epithelium, which proliferates and almost occludes the lumen
  • At weeks 6 - 7, submucosal plexus develops, circular muscular layer develops
  • At weeks 6 - 7, epithelial vacuolization appears, vacuoles coalesce to form a single esophageal lumen
  • At week 8, ciliated cells appear and extend to almost entire columnar epithelium
  • At week 9, longitudinal muscle layer develops; interstitial cells of Cajal appear
  • At week 10, a single layer of columnar cells covers entire esophagus
  • At month 4, submucosal glands appear due to downward growth of columnar cells, extend distally to cardiac mucosa
  • At month 5, stratified squamous epithelium initially appears in midesophagus and replaces ciliated epithelium cephalad and caudally; proximal esophagus may retain ciliated epithelium at birth
  • At month 5, upper esophagus has both striated and smooth muscle
Diagrams / tables

Images hosted on other servers:

4 weeks - relation of gut to yolk sac

Microscopic (histologic) images

Contributed by Dr. Grigory Demyashkin, I. M. Sechenov First Moscow State Medical University (Russia)

6 - 8 week embryo

Upper left: small intestine
bottom left: esophagus
center: stomach
top right: pancreas; right: liver

Top: spine
lower left: trachea amd esophagus
center: lung, glandular stage

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