Carnegie stage 5

Embryology - 1 Dec 2023        Expand to Translate
Google Translate - select your language from the list shown below (this will open a new external page)
العربية | català | 中文 | 中國傳統的 | français | Deutsche | עִברִית | हिंदी | bahasa Indonesia | italiano | 日本語 | 한국어 | မြန်မာ | Pilipino | Polskie | português | ਪੰਜਾਬੀ ਦੇ | Română | русский | Español | Swahili | Svensk | ไทย | Türkçe | اردو | ייִדיש | Tiếng Việt    These external translations are automated and may not be accurate. (More? About Translations)

Introduction

Facts: Week 1 - 2, size 0.1 - 0.2 mm Summary Implantation completed, inner cell mass, bilaminar embryo, trophoblast development, no villous development. See also Events The conceptus completes implantation during this stage. The trophoblast cells (syncytiotrophoblast and cytotrophoblast) proliferate. Syncytiotrophoblast cells continue to invade the maternal endometrium and cytotrophoblast cells form clumps that will later form sites of chorionic villi formation. The maternal endometrium locally begins the decidual process and the endometrial stroma accumulates fluid (edematous). The extraembryonic cavities begin to form. The bilaminar embryonic disc epiblast and hypoblast forms from the inner cell mass. Historical This stage was described as "Streeter Horizon V" and later sub-divided again into three separate sub-stages (a, solid trophoblast; b, trophoblastic lacunae; and c, beginning merolacunar circulation). Currently these are discussed as a single stage 5. The "embryonic disc" was called the "germ disc".

Week:	1	2	3	4	5	6	7	8
Carnegie stage:	1 2 3 4	5 6	7 8 9	10 11 12 13	14 15	16 17	18 19	20 21 22 23

Carnegie Stages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | About Stages | Timeline

Embryonic Disc

The "embryonic disc" was historically called the "germ disc", on the basis that it was the earliest stage (germinal) if the entire embryo. The lefthand image (day 12 Carnegie 7700) shows a cross-section detailed view of the bilaminar embryonic disc. The gallery below shows a number of different embryonic discs between 11 to 12 days.

• Embryonic Disc
• 

  Carnegie 7699 11 day

• 

  Carnegie 7950 12 day

• 

  Carnegie 7700 12 day

• 

  Carnegie 8558 12 day

• 

  Carnegie 8330 12 day

Animation

<html5media height="300" width="250">File:Chorion 001.mp4</html5media>	Animation (left) shows the events following implantation and focuses on changes in the the spaces surrounding the embryonic disc, the extraembryonic coelom. The blastoceol cavity is converted into two separate spaces: the yolk sac and the chorionic cavity. The third space lies above the epiblast, the amniotic cavity. blue - epiblast layer yellow - hypoblast layer red cells - extraembryonic mesoderm layer green - trophoblast layer red spaces - blood-filled spaces, maternal lacunae white cells - (left) endometrial gland (right) endometrial epithelium
Chorionic Cavity Movie | MP4 movie

Surface View

This is a uterine surface view showing the site of implantation (pale region in centre of image). The conceptus can be identified located at the dark central region within the pale region.

Carnegie Collection

Stage 5a

• Streeter Horizon Va
• 

  Carnegie 8225 7.5 day

• 

  Carnegie 8020 7.5 day

• 

  Carnegie 8155 8 day

• Carnegie 8155
• 

  Embryo No. 8155

• 

  Embryo No. 8155

• 

  Embryo No. 8155

Stage 5b

• Streeter Horizon Vb - 9 day
• 

  Carnegie 8215

• 

  Carnegie 8215 embryo, chorionic cavity and trophoblast

• 

  Carnegie 8171 predecidual reaction

• 

  Carnegie 8171 embryo and trophoblast

• 

  Carnegie 8004 endometrium and intact specimen

• 

  Carnegie 8004 embryo, chorionic cavity and trophoblast

• Embryo No. 8004
• 
• 
• 
• 

Stage 5c

• Streeter Horizon Vc - Surface and Cross-section view
• 

  Carnegie 7699 11 day

• 

  Carnegie 7950 12 day

• 

  Carnegie 7700 12 day

• Hertig1956 fig31-32.jpg

  Carnegie 855812-day

• 

  Carnegie 8330 12-day

• Carnegie Embryo 7699 (11 days)
• 

  Surface and implantation section

• 
• 
• 
• 
• 
• 

Carnegie Collection - Stage 5
Serial No.	Stage	Grade	Fixative	Embedding Medium	Thinness (µm)	Stain	Year	Notes
8020	5a	Exc.	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1942	Hertig and Rock (1945a)
8155	5a	Exc.	Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1943	Hertig and Rock (1949)
8225	5a	Exc.	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1944	Hertig and Rock (1945b)
8004	5b	Exc	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1942	Hertig and Rock (1945a)
8171	5b	Exc	Alc.	C-P	6	(Stain - Haematoxylin Eosin)	1943	Hertig and Rock (1949)
8215	5b	Exc	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1944	Hertig and Rock (1945c)
9350	5b	Exc	Bouin	?	?	(Stain - Haematoxylin Eosin)	1955	Heuser (1956)
4900	5c	Poor	p	P	10	p	1925	Incomplete. Streeter (1926)
7699	5c	Exc.	Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1939	Hertig and Rock (1941)
7700	5c	Exc.	Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1938	Hertig and Rock (1941)
7771	5c	Exc.	Bouin	C-P	10	(Stain - Haematoxylin Eosin)	1940	Abnormal
7950	5c	Exc.	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1941	Hertig and Rock (1944)
8000	5c	Poor	Alc. & Bouin	C-P	8	(Stain - Haematoxylin Eosin)	1942	Abnormal
8139	5c	Exc.	?	C-P	6	(Stain - Haematoxylin Eosin)	1943	Incomplete. Marchetti (1945)
8299	5c	Exc.	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin), phlox.	1945	Abnormal
8329	5c	Exc.	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin), phlox.	1945	Abnormal
8330	5c	Exc.	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin), phlox.	1945
8370	5c	Poor	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin), phlox.	1946	Abnormal
8558	5c	Exc.	Alc. & Bouin	C-P	6	(Stain - Haematoxylin Eosin)	1947
Stage 5 was originally subdivided into 3 sequential parts a, b, c. Abbreviations Grade - total grade of the specimen and includes both its original quality and the condition of the mounted sections. Embedding medium - paraffin (P) or a combination of celloidin and paraffin (C-P). Fixative - formalin (Formol), alcohol and formalin (Alc, formol), Bouin (Bouin solution) ? - unknown or not determined.
References

iBook - Carnegie Embryos

iTunes link | iBook Store Description - Imagine the excitement of seeing this incredible early period of human development for the first time. Now consider that much of our initial understanding of human development is based upon study of historic embryo collections. You can now look at these historic images of the first 8 weeks after fertilisation and explore for yourself the changes that occur in human development during this key period. This current book is designed as an atlas of the Carnegie embryo stages with some brief notes and additional information covering the first 8 weeks of development. These images are from from the beginning of last century and are one of the earliest documented series of human embryos collected for basic research and medical education on development. I hope you enjoy learning about the amazing early events that begin to make and shape us. This is the second book in a series of educational releases from UNSW Embryology. Release: First Edition - Mar 12, 2012 ISBN 978-0-7334-3148-7 Print Length 82 Pages, 25.8 MB Language English. PDF Preview version 3.87 MB (Read the associated information, this is an edited educational preview version with many features not functioning). The current website also includes numerous embryo images from this textbook (see Embryonic Development and Carnegie Embryos).

Historic Stage 5 Embryos

Historic stage 5 embryo data modified from O'Rahilly and Müller (1987).

Stage 5a

• Carnegie No. 8225 - Described briefly by Hertig and Rock (1945b). Hysterectomy (bicornuate uterus). Anterior wall of uterus. Chorion, 0.33 x 0.306 mm. Chorionic cavity, 0.228 x 0.2 mm. Embryonic disc, 0.09 x 0.078 mm. Perhaps more advanced than Carnegie No. 8020 (Mazanec, 1959; Harris and Ramsey, 1966), but has also been interpreted as less advanced. Photomicrograph in Hertig, Rock, and Adams (1956, fig. 9 and 10). Presumed age, 7 days.
• Carnegie No. 8020 - (figs. 5-3 to 5-5). Described by Hertig and Rock (1945a). Hysterectomy. Posterior wall of uterus. Chorion, 0.45 x 0.3 mm. Chorionic cavity, 0.288 x 0.186 mm. Embryonic disc, 0.126 x 0.092 mm. New model of blood vessels at implantation site has been prepared (Harris and Ramsey, 1966). Presumed age, 7 days.
• Fruhling, Ginglinger, and Gandar (1954) described briefly a specimen of about 8 days. Curettage. Early implantation. Few trophoblastic digitations. Beginning amniotic cavity. Most sections through embryonic disc lost.
• Carnegie No. 8155 - (fig. 14). Described by Hertig and Rock (1949). Hysterectomy. Anterior wall of uterus. Chorion, 0.306 x 0.210 mm. Chorionic cavity, 0.168 x 0.082 mm. Embryonic disc, 0.09 x 0.05 mm. “Tropho-epiblastic cavity” (Luckett, 1975).

Stage 5b

• Carnegie No. 8171 - Described by Hertig and Rock (1949). Hysterectomy. Posterior wall of uterus. Abnormal leucocytic infiltration of endometrium. Chorion, 0.422 x 0.404 mm. Chorionic cavity, 0.164 X 0.138 mm. Embryonic disc, 0.114 x 0.088 mm. A cellular remnant within the umbilical vesicle, because it is probably derived from the endoderm, “may, in a sense, be regarded as an abnormal form of twin embryo” (ibid.). Presumed age, 9 days.
• Carnegie No. 8215 - Described briefly by Hertig and Rock (1945c). Hysterectomy. Posterior wall of uterus. Chorion, 0.525 X 0.498 mm. Chorionic cavity, 0.228 X 0.21 mm. Embryonic disc, 0.084 x 0.052 mm. Lacunae perhaps further developed than in No. 8171 (Mazanec, 1959), but specimen has been “considered to be slightly younger because the decidual reaction is not yet apparent” (Hertig, Rock, and Adams, 1956). Photomicrographs in Hertig, Rock, and Adams (1956, figs. 15 and 17). Presumed age, 9 days.
• Carnegie No. 8004 - (figs. 5-7 to 5-9). Described by Hertig and Rock (1945a). Hysterectomy. Posterior wall of uterus. Chorion, 0.582 x 0.45 mm. Chorionic cavity, 0.312 X 0.185 mm. Embryonic disc, 0.132 x 0.1 mm.
• Carnegie No. 9350 - Described briefly by Heuser (1956). Hysterectomy. At junction of posterior and anterior walls. Chorion, 0.59 x 0.58 mm. Chorionic cavity, 0.3 X 0.1 mm. Embryonic disc, 0.132 x 0.09 mm. Presumed age, 9 days.

Stage 5c

"Macafee" embryo

• Macafee - Described by Morton (1949). Curettage. Probably belongs to stage 5. Embryonic disc not found.
• Davies-Harding - Described by Davies (1944). Hysterectomy. Anterior wall of uterus. Incomplete (almost one-half of embryonic disc missing). “No true villi.” Primary umbilical vesicle present. Extensive extra-embryonic meshwork. Slightly later stage of development than No. 8004 (Davies, 1944, Addendum), which belongs to 5b. “Possibly pathological” (Boyd and Hamilton, 1970). Chorion, 1.18 x 0.55 mm. Chorionic cavity, 0.409 x 0.238 mm. Embryonic disc, 0.117 mm. May be regarded as transitional between 5b and 5c. Presumed age, 9-10 days.
• Carnegie No. 7699 - Described by Hertig and Rock (1941). Hysterectomy. Posterior wall of uterus. Chorion, 1.026 x 0.713 mm. Chorionic cavity, 0.48 x 0.336 mm. Embryonic disc, 0.138 x 0.138 mm. New model of blood vessels at implantation site has been prepared (Harris and Ramsey, 1966). Presumed age, 11 days.
• Carnegie No. 4900 - Miller. Described by Streeter (1926). Curettage. Angiogenesis described by Hertig (1935). Incomplete (some sections missing). Primary umbilical vesicle present. New graphic reconstruction made by Streeter (1939a,b). Chorion, 0.9 mm. Chorionic cavity, 0.4 mm. Presumed age, 10-11 days or perhaps even 12 days (Krafka,1941).
• Dible-West. Described by Dible and West (1941). Autopsy. Posterior wall of uterus. Incomplete. Chorionic cavity, 0.47 x 0.28 mm. Embryonic disc, 0.1 x 0.02 mm. Presumed age, 11-13 days.
• Müller (1930) described an autopsy specimen. Only one section was near the embryonic disc.
• Wilson (1954) found a specimen by endometrial biopsy. Chorion, 0.5 x 0.6 mm. Chorionic cavity, 0.47 x 0.24 mm. Between the amnion and the cytotrophoblast, “a small accumulation of fibroblastic cells probably represents the earliest stage of the Bauchstiel.” The endoderm is described as being “delaminated from the embryonic disc.” Presumed age, 11 days.
• Carnegie No. 7950 - Described briefly by Hertig and Rock (1944). Chorion, 0.75 x 0.45 mm. Chorionic cavity, 0.4 x 0.26 mm. Embryonic disc, 0.16 x 0.07 mm. Slightly more developed than No. 7699, although embryo is a little less differentiated. Photomicrographs in Hertig, Rock, and Adams (1956; figs. 27 and 35). Presumed age, 12 days.
• Carnegie No. 7700 (figs. 18-22). Described by Hertig and Rock (1941). Hysterectomy. Posterior wall of uterus. Chorion, 0.948 x 0.835 mm. Chorionic cavity, 0.55 x 0.498 mm. Embryonic disc, 0.204 x 0.165 mm. Presumed age, 12 days.
• Carnegie No. 8558 - Measurements and photomicrographs in Hertig, Rock, and Adams (1956; figs. 30 and 37). Chorion, 0.96 x 0.52 mm. Chorionic cavity, 0.58 x 0.36 mm. Embryonic disc, 0.22 x 0.08 mm. Presumed age, 12 days.
• Carnegie No. 8330 - Measurements and photomicrographs in Hertig, Rock, and Adams (1956; figs. 30 and 37). Chorion, 0.85 x 0.65 mm. Chorionic cavity, 0.46 x 0.4 mm. Embryonic disc, 0.216 x 0.063 mm. Condensation of extra-embryonic mesoblast perhaps indicates “the beginning of axis formation” (ibid.). Presumed age, 12 days.
• Kleinhans - Described by Grosser (1922). Autopsy. Only one section. Embryonic disc not seen. Chorion, 0.8 x 0.65 mm. Chorionic cavity, 0.35 x 0.15 mm.
• Barnes - Described by Hamilton, Barnes, and Dodds (1943), and further by Hamilton and Boyd (1960). Hysterectomy. Posterior wall of uterus. Pathological edema in endometrium (Davies, 1944). Chorion, 0.931 x 0.77 x 0.737 mm. Primary umbilical vesicle and perhaps early differentiation of secondary vesicle (Luckett, 1978). Presumed age, 10-11 days or perhaps 12 days (Davies, 1944).
• Werner - (Prof. Werner Gerlach). Described by Stieve (1936), with graphic reconstruction by Florian. Autopsy. Chorion, 0.78 x 1.36 x 0.72 mm. Embryonic disc, 0.18 x 0.12 mm. Some large, round cells in the epiblast are mentioned as possible primordial germ cells. Primary umbilical vesicle and perhaps early differentiation of secondary vesicle (Luckett, 1978). Primordia (mesoblastic crests) of chorionic villi (Hertig and Rock, 1941). ‘Connecting stalk’ very indistinct. Rostrocaudal axis but no primitive streak; epiblast fused with extra-embryonic mesoblast caudally and perhaps is origin of latter (Florian, 1933 and 1945). Perhaps 12 days.
• Knoth and Larsen (1972) studied an implantation site by electron microscopy. No villi, but “beginning” to form. Primary umbilical vesicle “not so easily seen.” Probably 11 days.
• Dankmeijer and Wielenga (1968) described a specimen of stage 5. Curettage. Incomplete.
• Carnegie No. 8139. Described by Marchetti (1945), who admitted that it is “not entirely normal.” Curettage. Chorion, 0.706 x 1.2 mm. Chorionic cavity, 0.635 x 0.582 mm. Embryonic disc, 0.126 x 0.048 x 0.116 mm. Embryo located centrally in chorionic cavity, which contains a meshwork. Embryonic disc, slightly ovoid (i.e., presents a longitudinal axis). Described originally as previllous, although “primitive villi” (stage 6) are mentioned by Boyd and Hamilton (1970): folds of undulating contour of cytotrophoblast are not yet “primitive unbranching villi, although they may be the primordial of them” (Marchetti, 1945; fig. 5). Primary umbilical vesicle present. May be regarded as transitional between stages 5 and 6. Presumed age, 13 days.
• Bandler (1912) found a specimen embedded in tubal mucosa and which showed “as yet absolutely no suggestion of chorionic villi.” No details available.
• Pommerenke (1958) described a specimen of stage 5. Curettage. Incomplete. Embryo not included.
• Scipiades (1938) described a specimen that belongs either to stage 5 or to stage 6, probably the former, “but its preservation is so poor that accurate conclusions are impossible” (Hertig and Rock, 1941). Curettage. Chorion, 1.498 x 0.49 mm. Chorionic cavity, 0.99 mm. Embryonic disc (only two sections available), 0.18 x 0.048 mm. Presumed age, 11-12 days.
• Thomas and van Campenhout (1963) found a specimen that probably belongs to stage 5, although some trophoblastic thickenings of a villous character were said to be present.
• Teacher-Bryce I. A pathological specimen of stage 5 described by Bryce (1924).
• Sch. (Schönig). A pathological specimen of stage 5 described by von Möllendorff (1921a).
• Keller and Keller (1954) found a pathological specimen embedded in the stroma of the ostium uteri.

Several pathological specimens of stage 5c are in the Carnegie Collection. Nos. 8370, 7770, 8299 (malpositioned embryonic disc, Hertig, 1968, fig. 132), 8329, 8000 (superficial implantation), and 7771 (no embryo) were measured and illustrated by Hertig, Rock, and Adams (1956).

Events

• Mitosis - cells on surface of blastocyst (trophoblast cells) divide more rapidly than the inner cells (inner cell mass, embryoblast)
• Implantation - adhesion to endometrium epithelium and implantation through this layer into the underlying uterine storm.
• Endocrine signalling - trophoblast cells secrete hCG (human Chorionic Gonadotropin/Gonadotrophin) the signal of pregnancy.
• Cell invasion and fusion - trophoblast cells spread through the maternal uterine wall and also fuse together to form specialised multi-nucleated cells.
• Corpus luteum - signal from trophoblasts maintain this endocrine tissue in the maternal ovary that secretes progesterone.

References

Carnegie Stages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | About Stages | Timeline

Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link

---

Cite this page: Hill, M.A. (2023, December 1) Embryology Carnegie stage 5. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Carnegie_stage_5

What Links Here?

© Dr Mark Hill 2023, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G