title: Laser-assisted removal of necrotic blastomeres from cryopreserved embryos that were partially damaged.
abstract: OBJECTIVE
  To examine whether the developmental potential of embryos that were partially damaged after freezing and thawing can be improved by removal of necrotic blastomeres before embryo transfer.
  
  
  METHODS
  Prospective pilot study and observational clinical series.
  
  
  METHODS
  Private hospital.
  
  
  METHODS
  Two hundred thirty-five infertile couples undergoing frozen embryo transfer.
  
  
  METHODS
  Removal of necrotic blastomeres from frozen-thawed human embryos.
  
  
  METHODS
  Pregnancy and implantation rates.
  
  
  RESULTS
  Removal of necrotic blastomeres from partially damaged frozen-thawed embryos before transfer increased rates of pregnancy (45.7% vs. 17.1%), ongoing pregnancy (40.0% vs. 11.4%) and ongoing implantation (16.2% vs. 4.3%) compared with the control group, in which necrotic blastomeres were not removed. A similarly high implantation rate (16.7%) was seen a subsequent clinical series in which necrotic blastomeres were removed from all partially damaged embryos.
  
  
  CONCLUSIONS
  The viability of partially damaged frozen-thawed embryos can be improved by removal of necrotic blastomeres before embryo transfer.
authors.affiliation: Centre for Reproductive Medicine, European Hospital, Rome, Italy. laura@libero.it
authors.forename: Laura
authors.initials: L
authors.lastname: Rienzi
authors.forename: Zsolt Peter
authors.initials: ZP
authors.lastname: Nagy
authors.forename: Filippo
authors.initials: F
authors.lastname: Ubaldi
authors.forename: Marcello
authors.initials: M
authors.lastname: Iacobelli
authors.forename: Reno
authors.initials: R
authors.lastname: Anniballo
authors.forename: Jan
authors.initials: J
authors.lastname: Tesarik
authors.forename: Ermanno
authors.initials: E
authors.lastname: Greco
mesh_terms: D000328:Adult; D001757:Blastomeres / Q000473:pathology* / Q000528:radiation effects*; D015925:Cryopreservation; D010064:Embryo Implantation; D004622:Embryo, Mammalian / Q000473:pathology* / Q000502:physiology; D005260:Female; D006801:Humans; D007834:Lasers; D009336:Necrosis; D010865:Pilot Projects; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies