Implantation (embryology)
Videos
Implantation, also known as nidation, is the stage in the mammalian embryonic development in which the blastocyst hatches, attaches, adheres, and invades into the endometrium of the female's uterus. I
Diagram of stages of developing blastocyst in the human until implantation
Illustration of an implanting embryo
Early formation of placenta
Fetal-maternal interface showing uterine milk
Embryo
Videos
An embryo is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilizati
Implantation (embryology)
…of the female's uterus. Implantation is the first stage of gestation, and, when successful, the female is considered to be pregnant. An implanted embryo is detected by the presence of increased levels of human chorionic gonadotropin (hCG) in a pregnancy test. The implanted embryo will receive oxygen and…
A human embryo seven weeks after conception (nine weeks gestational age)
Embryos (and one tadpole) of the wrinkled frog (Rana rugosa)
Mouse and snake embryos
The inside of a Ginkgo seed, showing the embryo