Zona hatching
Zona hatching is a phenomenon occurring during prenatal development. Prior to this event, the predecessor of the embryo, in the form of a blastocyst, is surrounded by a glycoprotein sphere called the zona pellucida. To be able to perform implantation on the uterine wall, the blastocyst first needs to get rid of the zona pellucida.[1] This lysis of the zona pellucida is called the zona hatching.[2] In humans, this happens at the end of day four.[3]
Uses of the term
In some situations, the term "hatching" is used only for artificial ways to free the blastocyst from the zona pellucida, and not the natural lysis of it. An example of such artificial way is assisted zona hatching.
References
- ↑ IVF-infertility.com
- ↑ Hill, Mark. "Blastocyst Development". UNSW Embryology. UNSW CRICOS. ISBN 978-0-7334-2609-4.
- ↑ Langman's Medical Embryology 6th Edition, page 46
This article is issued from Offline. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.