Human Embryo Collections

Introduction

While many universities hold collections of embryos from many species, very few have well-characterised collections of embryos showing human development. Many of those that are available are historic in nature, consist of histological sections, some with limited information about the embryo history.

There are groups now taking advantage of new imaging techniques to either re-evaluate these historic collections, or analysing new embryonic material. Some of these new databases are being made available online for research purposes.

Remember that this current site is for educational use only.

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

Carnegie Collection

Carnegie Embryos

(Carnegie Institution, USA)

Begun by Franklin Mall in the early 1900's.
Many of these embryos were used in the historic papers in the Contributions to Embryology series - Carnegie Institution of Washington Series.

Kyoto Collection

Kyoto Embryos

(Kyoto University, Japan)

Begun by Dr. Hideo Nishimura in 1961 and has over 44,000 human embryo specimens.
Polydactyly in human embryos^[1]
- 129 embryos with polydactyly in 36,380 human conceptuses obtained through induced abortion during the period from 1962 to 1974.
Human embryo imaging with a super-parallel magnetic resonance (MR) microscope^[2]

Links: Kyoto Collection

Hamilton-Boyd Collection

Boyd collection placenta section

(Cambridge University, UK)

Collected by Professor JD Boyd, Professor of Anatomy at the University in the 1950s and 1960s.
Held at the University of Cambridge.
Professor Boyd wrote the monographs 'Human Embryology' (Hamilton, Boyd and Mossman) and 'The Human Placenta' (Boyd and Hamilton).
Collection is only histological sections (no tissue blocks remain)

Links: Boyd Collection

Blechschmidt Collection

Blechschmidt model on display.

(University of Goettingen, Germany)

Erich Blechschmidt (1904–92) independently developed new methods of embryo reconstruction.
Director of Göttingen University’s Anatomical Institute from 1942 until 1973.
200,000 serial sections of embryos and 64 models.
Professor E. Blechschmidt embryological collection were assigned Carnegie Nos. 10315-10434 in 1972.
- Professor Blechschmidt's wish was to have his collection combined with the Carnegie Collection.

Links: The Human Embryology Collection | Collections of the University Medical Center

Central Laboratory for Human Embryology

(University of Washington, USA)

begun August 1963.
after 18years consists of 5,200 specimens.
range from very young embryos to full-term fetus.

Ziegler Models

Not a collection as such, but a historic series of wax models made in the 1880s based upon the embryos of Prof. Wilhelm His, Leipzig. His had earlier prepared a series of freehand models. These models are still the basis of some teaching models used today.

The Carnegie Institute later in the early 1900's developed many additional models. (More? Carnegie Models)

Carnegie Stage Table

Weeks shown in the table below are embryonic post ovulation age, for clinical Gestational Age (GA) measured from last menstrual period, add 2 weeks.

Stage	Days (approx)	Size (mm)	Images (not to scale)	Events
1	1 (week 1)	0.1 - 0.15		fertilized oocyte, zygote, pronuclei
2	2 - 3	0.1 - 0.2		morula cell division with reduction in cytoplasmic volume, blastocyst formation of inner and outer cell mass
3	4 - 5	0.1 - 0.2		loss of zona pellucida, free blastocyst
4	5 - 6	0.1 - 0.2		attaching blastocyst
5	7 - 12 (week 2)	0.1 - 0.2		implantation
6	13 - 15	0.2		extraembryonic mesoderm, primitive streak, gastrulation
7	15 - 17 (week 3)	0.4		gastrulation, notochordal process
8	17 - 19	1.0 - 1.5		primitive pit, notochordal canal
9	19 - 21	1.5 - 2.5		Somitogenesis Somite Number 1 - 3 neural folds, cardiac primordium, head fold
10	22 - 23 (week 4)	2 - 3.5		Somite Number 4 - 12 neural fold fuses
11	23 - 26	2.5 - 4.5		Somite Number 13 - 20 rostral neuropore closes
12	26 - 30	3 - 5		Somite Number 21 - 29 caudal neuropore closes
13	28 - 32 (week 5)	4 - 6		Somite Number 30 leg buds, lens placode, pharyngeal arches
Stage 13/14 shown in serial embryo sections series of Embryology Program
14	31 - 35	5 - 7		lens pit, optic cup
15	35 - 38	7 - 9		lens vesicle, nasal pit, hand plate
16	37 - 42 (week 6)	8 - 11		nasal pits moved ventrally, auricular hillocks, foot plate
17	42 - 44	11 - 14		finger rays
18	44 - 48 (week 7)	13 - 17		ossification commences
19	48 - 51	16 - 18		straightening of trunk
20	51 - 53 (week 8)	18 - 22		upper limbs longer and bent at elbow
21	53 - 54	22 - 24		hands and feet turned inward
Stage 22 shown in serial embryo sections series of Embryology Program
22	54 - 56	23 - 28		eyelids, external ears
23	56 - 60	27 - 31		rounded head, body and limbs
Following this stage Fetal Development occurs until birth (approx 37 weeks)