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

The 4-Week Embryo

#368, Slide 57 of 312

3 weeks, 4 days

From The Biology of Prenatal Development.Buy Now

Label Key:

1. brain
2. body cavities
3. somites
4. tail
All ages referenced to fertilization, not last menstrual period.
Tell your story. Create your own pregnancy calendar.
When does health begin? Find out now.