Week 1

Key Events of Human Development during the first week (week 1) following fertilization or Clinical week 3 (LMP).

Day	Stage	Event
1	Secretory PhaseStage 1	Fertilization, Secretory Phase
2	Stage 2	Morula, Blastula
3
4	Stage 3	Blastocyst Hatching (zona pellucida lost)
5		Blastocyst (free floating)
6	Stage 4	Adplantation
7	Stage 5	File:2ndwk.jpg

Embryo Week: Week 1 | Week 2 | Week 3 | Week 4 | Week 5 | Week 6 | Week 7 | Week 8 | Week 9

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

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Cite this page: Hill, M.A. (2024, May 4) Embryology Week 1. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Week_1

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G