title: Hormonal stimulation for in vitro fertilization: a comparison of fertilization rates and cytogenetic findings in unfertilized oocytes.
abstract: OBJECTIVE
  The purpose of this study was to compare fertilization and aneuploidy rates after two stimulation protocols in an IVF program.
  
  
  METHODS
  This was a retrospective study.
  
  
  METHODS
  The study took place in the IVF laboratory of an Infertility Department.
  
  
  METHODS
  In 349 treatment cycles, clomiphene citrate (CC) and human menopausal gonadotropin (hMG) were used in one group (N = 233) and hMG after treatment with a gonadotropin-releasing hormone agonist (GnRHa) in two other groups (long protocol): goserelin (N = 73) and buserelin (N = 43). Cytogenetic analysis was performed on all unfertilized oocytes in both groups.
  
  
  RESULTS
  Fertilization rates were significantly higher in the GnRHa/hMG group than in the CC/hMG group, but cleavage rates and embryo quality were not different. Of 736 oocytes prepared for cytogenetic analysis, 256 were karyotyped: 172 were found to be euploid and 84 aneuploid. More oocytes were aneuploid in the GnRHa/hMG group than in the CC/hMG group and this difference was statistically different after analysis of the data using a specially designed mathematical model.
  
  
  CONCLUSIONS
  If no selection against chromosomally abnormal oocytes takes place at the time of fertilization, more abnormal oocytes are harvested with GnRHa/hMG protocols than with CC/hMG. If, on the other hand, there is a selection against oocytes with some chromosomal imbalance, there is no intrinsic effect of GnRH agonists on the chromosomal complement of the oocyte, and the real aneuploidy frequency in all oocytes, fertilized and unfertilized, is the same in the GnRHa/hMG and in the CC/hMG group.
authors.affiliation: Department of Gynecology and Obstetrics, State University of Ghent, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: De Sutter
authors.forename: M
authors.initials: M
authors.lastname: Dhont
authors.forename: D
authors.initials: D
authors.lastname: Vandekerckhove
mesh_terms: D000782:Aneuploidy; D002478:Cells, Cultured; D002970:Cleavage Stage, Ovum / Q000187:drug effects*; D046508:Culture Techniques; D003692:Delayed-Action Preparations; D004622:Embryo, Mammalian / Q000187:drug effects*; D005260:Female; D005307:Fertilization in Vitro / Q000187:drug effects*; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D006801:Humans; D007621:Karyotyping; D009865:Oocytes / Q000187:drug effects; D010062:Ovulation Induction / Q000379:methods*; D017329:Triptorelin Pamoate / Q000031:analogs & derivatives*
chemical_list: D003692:Delayed-Action Preparations; D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone; C019176:Tryptal