Skip Navigation
The Endowment for Human Development
The Endowment for Human Development
Improving lifelong health one pregnancy at a time.
  • English
Español
Português
Educator Login / Register
Donate Now Get Free Videos

Slideshow: Entire Image Gallery by EHD

Four-Cell Human Embryo

#13, Slide 19 of 312

48 hours

From The Biology of Prenatal Development.Buy Now

Label Key:

1. perivitelline space
2. zona pellucida
3. blastomeres
All ages referenced to fertilization, not last menstrual period.
Free resources and training for educators
Help give babies a healthy start and a healthy future. Donate now.