Oocyte Morphology
All eggs are not the same!
Have you heared your doc say "immature eggs", "poor eggs" etc?
Well, it's not unusual for some of the oocytes collected at the egg pick up to be unsuitable for fertilization ( and remember not all your eggs fertilized). Think twice if ever asked to donate eggs to another couple! link
Superovulation aims to produce a certain number of nice eggs-the time of egg collection is important to harvest a suitable number of eggs. This is determined my size of follicles (on an ultrasound) and hormone levels (eostrodiol blood test).
A nice egg or oocyte should have:
Mature outer cells to allows sperm to weave their way towards the egg.
Mature outer jelly coat to allow the entry of only one sperm.
Mature cell at the correct stage of development containing half the genetic material (to fuse with the sperm containing the other half) giving rise to an embryo ( a mix a both parents)
Anatomy of an egg:
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the cytoplasm- the main mass of the egg, the cellular material,
DNA and energy store are housed here
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The polar body- indicates the egg is at the correct stage for
fertilization ( contains the excess DNA material)
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The cummulus cells-surround the egg after ovulation and
gradually are dispersed
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The zona pellucida- jelly like coating of the egg and developing
embryo
Immature eggs
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The egg with no polar body
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The germinal vesical-indicates the egg is very immature and
will not fertilize
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The germinal vesical- has not completed cell division to contain
half the genetic material
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The germinal vesical-the inner circle containing the chromosomes
Abnormal eggs
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The egg with abnormal shape
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The egg with vacuoles -fluid sacs for discarding cellular matter
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The egg with abnormal cytoplasm
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The egg with abnormal polar body
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The egg with no zona
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Empty zona-only zona pellucida remains after egg degenerates
