title: Limiting the number of injected oocytes to three impairs ICSI outcomes in patients with nonobstructive azoospermia.
abstract: BACKGROUND
  Since March 2004, only a maximum of three oocytes were allowed to be subjected to ICSI at one time in Italy. A previous study failed to show an impact of this restriction on fresh embryo transfer outcomes. The objective of this study was to compare ICSI outcomes before and after this restriction in patients with nonobstructive azoospermia.
  
  
  METHODS
  Patients underwent testicular sperm extraction followed by ICSI. Biological (fertilization rate and the percentage of good-morphology zygotes and embryos) and clinical (clinical pregnancy and implantation rates) outcomes of the last 100 ICSI attempts before the restriction and outcomes of the first 100 ICSI attempts after the restriction were compared.
  
  
  RESULTS
  Despite comparable fertilization rates (58.8% versus 59.2%; P > 0.05), there was a significant decrease in the percentage of good-morphology zygotes (41.1% versus 88.4%; P < 0.05) and embryos (36.7% versus 74.0%; P < 0.05) in the cohort of embryos transferred, clinical pregnancy rate (22.7% versus 42.4%; P < 0.05) and cumulative pregnancy rate from fresh and frozen embryo transfers (22.7% versus 53.5%; P < 0.05) after the restriction.
  
  
  CONCLUSIONS
  The oocyte number restriction reduces dramatically the chance of achieving a clinical pregnancy in cases of nonobstructive azoospermia.
authors.affiliation: Centre for Reproductive Medicine, European Hospital, Rome, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Greco
authors.forename: F
authors.initials: F
authors.lastname: Ubaldi
authors.forename: L
authors.initials: L
authors.lastname: Rienzi
authors.forename: M
authors.initials: M
authors.lastname: Iacobelli
authors.forename: S
authors.initials: S
authors.lastname: Ferrero
authors.forename: G
authors.initials: G
authors.lastname: Minasi
authors.forename: S
authors.initials: S
authors.lastname: Romano
authors.forename: C
authors.initials: C
authors.lastname: Litwicka
authors.forename: Jan
authors.initials: J
authors.lastname: Tesarik
mesh_terms: D000328:Adult; D015331:Cohort Studies; D004624:Embryo Transfer; D005260:Female; D006801:Humans; D008297:Male; D009845:Oligospermia / Q000628:therapy*; D009865:Oocytes / Q000378:metabolism; D010062:Ovulation Induction; D011247:Pregnancy; D011256:Pregnancy Outcome; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*; D013094:Spermatozoa / Q000378:metabolism; D013737:Testis / Q000378:metabolism; D016896:Treatment Outcome