title: Efficiency of laser-assisted intracytoplasmic sperm injection in a human assisted reproductive techniques program.
abstract: OBJECTIVE
  Laser-assisted intracytoplasmic sperm injection (LA-ICSI), also known as micro-opening or thinning of the zona pellucida (ZP) prior to ICSI, may help to reduce mechanical damage to the oocyte during the procedure. The aim of the present study was to evaluate and analyze the efficacy of our institutional LA-ICSI program, which features laser-assisted ZP thinning prior to ICSI, in comparison with conventional ICSI (C-ICSI), performed on patients with different clinical characteristics.
  
  
  METHODS
  Patients undergoing a total of 212 ICSI cycles were randomly divided into an LA-ICSI group (106 cycles) and a conventional ICSI group (106 cycles). To reduce tissue damage, we thinned the ZP by approximately 70%, using a laser, before ICSI. Patients thus treated formed the LA-ICSI group. Comparisons included the morphological quality of transferred embryos, blastocyst development of the remaining embryos, and clinical pregnancy, in terms of ICSI method and patient characteristics.
  
  
  RESULTS
  Fertilization, development of remaining embryos, and pregnancy rate were significantly higher in the LA-ICSI group compared with the C-ICSI group. Fertilization, embryonic development, and the pregnancy rate were all improved in younger patients (<38 years of age) and in those who underwent a low number of IVF-ET attempts (<3 trials). In addition, the pregnancy rate was increased in older patients.
  
  
  CONCLUSIONS
  LA-ICSI may be useful in improving the chance of pregnancy in all ICSI patients.
authors.affiliation: Fertility Center of CHA Gangnam Medical Center, CHA University College of Medicine, Seoul, Korea.
authors.forename: Kyoung Hee
authors.initials: KH
authors.lastname: Choi
authors.forename: Jung Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Yun Hee
authors.initials: YH
authors.lastname: Yang
authors.forename: Tae Ki
authors.initials: TK
authors.lastname: Yoon
authors.forename: Dong Ryul
authors.initials: DR
authors.lastname: Lee
authors.forename: Woo Sik
authors.initials: WS
authors.lastname: Lee