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Intermediate Technical IVT

oocyte

Pronunciation: OH-oh-site

The female reproductive cell; an immature egg cell retrieved during fertility treatments or naturally released during ovulation.

Full Definition

An oocyte is the female gamete or egg cell at various stages of development within the ovarian follicle. In reproductive medicine contexts, the term specifically refers to the cell retrieved during egg collection procedures for in vitro fertilization or other assisted reproductive technologies. Oocytes are classified by their maturity level: immature (germinal vesicle stage), intermediate (metaphase I), or mature (metaphase II, ready for fertilization). The quality and number of oocytes retrieved are critical factors in determining the success rates of fertility treatments, and oocyte viability directly impacts embryo development potential.

Usage

Usage note: Preferred term in clinical documentation over 'egg' for precision.

In Context

  • "Fifteen oocytes were retrieved during the egg collection procedure." — Surgical report
  • "Only twelve of the retrieved oocytes were mature and suitable for fertilization." — Laboratory report

Also known as

egg cell ovum

Contrasted with

sperm

Don't confuse with

embryo zygote

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