cumulus-oocyte complex
Also written as: COC
The structure consisting of an egg cell surrounded by supporting cumulus cells, retrieved during egg collection procedures.
Full Definition
A cumulus-oocyte complex (COC) is the natural structure consisting of an oocyte surrounded by a layer of specialized granulosa cells called cumulus cells. These supporting cells play a crucial role in oocyte maturation, providing nutrients and growth factors essential for egg development. During assisted reproductive technology procedures, COCs are retrieved from ovarian follicles during egg collection. The presence and quality of cumulus cells can indicate oocyte maturity and developmental potential. Before intracytoplasmic sperm injection (ICSI), cumulus cells are typically removed to allow direct access to the oocyte, while for conventional IVF, they may be left partially intact as they can facilitate sperm binding and fertilization.
Usage
Usage note: Often abbreviated as COC in laboratory documentation; maintain consistency.
In Context
- "Twenty cumulus-oocyte complexes were retrieved and assessed for maturity." — Laboratory report
- "Cumulus cell removal revealed twelve mature oocytes suitable for ICSI." — Embryology report