Skip Navigation
The Endowment for Human Development
The Endowment for Human Development
Improving lifelong health one pregnancy at a time.
Donate Now Get Free Videos

Image Gallery

Three-Cell Embryo

40 hours

Source: Centro Riproduzione Assistita, Catania, Italy.

Label Key:

1. blastomere #1
2. blastomere #2
3. blastomere #3
4. perivitelline space
5. zona pellucida
6. polar body
All ages referenced to fertilization, not last menstrual period.
Two-Cell Human Embryo
Two-Cell Human Embryo
Two-Cell Embryo
Two-Cell Embryo
Three-Cell Embryo
Three-Cell Embryo
Four-Cell Human Embryo
Four-Cell Human Embryo
Four-Cell Embryo
Four-Cell Embryo
Five-Cell Embryo
Five-Cell Embryo
Help give babies a healthy start and a healthy future. Donate now.
Free resources and training for educators