Implantation

Definition

Implantation is the process by which a fertilized egg (embryo) attaches itself to the wall of the uterus to begin pregnancy. This critical step occurs about one week after fertilization and marks the start of the embryo's growth within the uterine environment.

Related terms

Fertilization:

The union of an egg and sperm cell that triggers the development of a new organism.

Uterus:

A female reproductive organ where implantation takes place and where the fetus develops during pregnancy.

Embryo:

An early stage of development for multicellular organisms following fertilization and before becoming a fetus