|In Vitro Fertilization (IVF) depends on upon the procurement of mature metaphase II oocytes, fertilization and persistence of the fertilized oocyte to the cleavage or blastocyst stage of embryonic development. At the inception of IVF, fruitful fertilization was entirely reliant upon the ability of ejaculated sperm to penetrate the outer boundaries of the oocyte, with the corona radiata (outer layer of cells surrounding the oocyte) and the zonal pellucida. The zona pellucida, which is the oocyte main boundary, permits or inhibits sperm from releasing its genetic material in to the cytoplasm (ooplasm) of the oocyte.
A journal is a periodical publication intended to further progress of science, usually by reporting new research. Most journals are highly specialized, although some of the oldest journals publish articles, reviews, editorials, short communications, letters, and scientific papers across a wide range of scientific fields. Journals contain articles that peer reviewed, in an attempt to ensure that articles meet the journal's standards of quality, and scientific validity. Each such journal article becomes part of the permanent scientific record.