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

Movie Theater

Human Development


7 days

From The Biology of Prenatal Development.Buy Now

Script: Biologically speaking, "human development begins at fertilization," when a woman and a man each combine 23 of their own chromosomes through the union of their reproductive cells.

All ages referenced to fertilization, not last menstrual period.
See Snapshots   |   Log in to create a playlist
Amnion and Germ Layers
Amnion and Germ Layers
Early Embryonic Development
Early Embryonic Development
Human Development
Human Development
Heart and Circulatory System
Heart and Circulatory System
The Folding of the Embryo
The Folding of the Embryo
The Folding of the Embryo
The Folding of the Embryo
Help give babies a healthy start and a healthy future. Donate now.
When does health begin? Find out now.