Compaction
Pronunciation: kom-PAK-shun
The embryonic process where individual blastomeres lose distinct borders and form a tightly packed cell mass.
Full Definition
Compaction is a crucial developmental milestone that typically occurs on day 4 of embryonic development, marking the transition from cleavage stage to morula. During this process, individual cells (blastomeres) increase their adhesion and lose visible cell boundaries, forming a compact spherical structure. Compaction indicates proper embryonic gene activation and cell-to-cell communication. Embryos that fail to compact by day 4 have reduced developmental potential. This process precedes cavitation and blastocyst formation, making it an important quality assessment parameter in extended embryo culture protocols.
Usage
Usage note: Critical timing marker for embryo selection in extended culture protocols.
In Context
- "Compaction was observed on schedule, indicating normal embryonic development." — Day 4 embryology report
- "Failed compaction on day 4 suggested compromised developmental potential." — Quality assessment note