| Inner cell mass | |
|---|---|
 Blastocyst with an inner cell mass and trophoblast | |
| Details | |
| Carnegie stage | 3 |
| Days | 6 |
| Precursor | Blastocyst |
| Gives rise to | Epiblast, hypoblast |
| Identifiers | |
| Latin | embryoblastus; massa cellularis interna; pluriblastus senior |
| MeSH | D053624 |
| TE | cell mass_by_E6.0.1.1.2.0.4 E6.0.1.1.2.0.4 |
| FMA | 86557 |
| Anatomical terminology | |
The inner cell mass (ICM) or embryoblast (known as the pluriblast in marsupials) is a structure in the early development of an embryo. It is the mass of cells inside the blastocyst that will eventually give rise to the definitive structures of the fetus. The inner cell mass forms in the earliest stages of embryonic development, before implantation into the endometrium of the uterus.[1] The ICM is entirely surrounded by the single layer of trophoblast cells of the trophectoderm.
- ^ Gilbert, Scott F. (2000). "Early Mammalian Development". Developmental Biology. 6th edition. Retrieved 13 May 2022.