Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1999-2-24
pubmed:abstractText
In human in-vitro fertilization (IVF), the oocytes are surrounded by cumulus and corona cells at the time of insemination so that their maturity cannot easily be evaluated. The best IVF results are obtained if the oocytes are inseminated 2-6 h after retrieval. In the intracytoplasmic sperm injection (ICSI) procedure, the oocytes are denuded by enzymatic and mechanical treatment in order to be able to perform the injection. As a consequence, the nuclear maturity of the oocytes can be evaluated and only those that have extruded the first polar body are injected. However, metaphase-II oocytes that have not yet reached cytoplasmic maturity cannot be recognized. The purpose of this study was to investigate the effect of different timing of cumulus-corona cell removal and injection on the outcome of ICSI. For this we allowed the oocytes to complete in-vitro cytoplasmic maturation in two different culture conditions: (i) surrounded by their cumulus and corona cells or (ii) totally denuded. We performed three different studies on sibling oocytes obtained after a standardized buserelin/human menopausal gonadotrophin (HMG) protocol. We investigated the effect of early (1-2 h after retrieval) and late (5-6 h after retrieval) oocyte denudation and injection on the survival and fertilization of the injected oocytes and on embryo cleavage after fertilization. We found no statistically significant differences between early and late injection, indicating that after a standardized buserelin/HMG protocol the metaphase-II oocytes do not need time for further cytoplasmic maturation. Furthermore, a different timing of cumulus-corona cell removal has no effect on the outcome of ICSI, suggesting that the surrounding cells are not necessary for survival, fertilization and cleavage after ICSI.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0268-1161
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3160-4
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Effect of timing of oocyte denudation and micro-injection on survival, fertilization and embryo quality after intracytoplasmic sperm injection.
pubmed:affiliation
Centre for Reproductive Medicine, Dutch-speaking Brussels Free University, Belgium.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't