title: Type of stimulation protocol affects oocyte maturity, fertilization rate, and cleavage rate after intracytoplasmic sperm injection.
abstract: OBJECTIVE
  To compare oocyte maturity, fertilization rate and cleavage rate after a short and long GnRH agonist (GnRH-a) stimulation protocol and intracytoplasmic sperm injection (ICSI).
  
  
  METHODS
  Retrospective study of 34 sequential ICSI cycles stimulated with a short or long GnRH-a protocol.
  
  
  METHODS
  A university-based tertiary care center for assisted reproductive treatment.
  
  
  RESULTS
  Significantly more oocytes were mature (metaphase II) after a long GnRH-a protocol then after a short GnRH-a protocol (25.6% and 80.8%, respectively). The long protocol resulted in more cleaving embryos (36/152 versus 9/132) and more cycles of ET (12/17 versus 5/17) than the short group.
  
  
  CONCLUSIONS
  A greater percentage of mature oocytes results from ovarian stimulation with a long GnRH-a protocol than a short GnRH-a protocol. Maturity could be assessed accurately after cumulus stripping that is required before ICSI. Fertilization rate and cleavage rate with ICSI was superior after a long GnRH-a stimulation protocol for superovulation.
authors.affiliation: Toronto Centre for Advanced Reproductive Technology, Ontario, Canada.
authors.forename: E M
authors.initials: EM
authors.lastname: Greenblatt
authors.forename: J S
authors.initials: JS
authors.lastname: Meriano
authors.forename: R F
authors.initials: RF
authors.lastname: Casper
mesh_terms: D000328:Adult; D002970:Cleavage Stage, Ovum; D003593:Cytoplasm; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D007248:Infertility, Male / Q000628:therapy*; D016729:Leuprolide / Q000008:administration & dosage / Q000627:therapeutic use; D008297:Male; D008596:Menotropins / Q000008:administration & dosage / Q000627:therapeutic use; D008845:Microinjections; D008875:Middle Aged; D009865:Oocytes / Q000502:physiology* / Q000648:ultrastructure; D010062:Ovulation Induction / Q000379:methods*; D012189:Retrospective Studies; D013094:Spermatozoa
chemical_list: D008596:Menotropins; D016729:Leuprolide