title: Fertilization by intracytoplasmic sperm injection (ICSI) does not impair subsequent pregnancy outcome following frozen embryo transfer (ET) as determined by a large retrospective analysis.
abstract: OBJECTIVE
  To determine if fertilization by intracytoplasmic sperm injection (ICSI) adversely affects pregnancy outcome following frozen embryo transfer (ET).
  
  
  METHODS
  Retrospective analysis of frozen ETs where the oocytes were fertilized by conventional insemination vs ICSI was carried out.
  
  
  RESULTS
  No difference in pregnancy outcome was found in women up to age 42. There was a non-significant trend for lower pregnancy rates in women age 43 and older.
  
  
  CONCLUSIONS
  In the largest series to date by far these data convincingly show that fertilization by ICSI does not impair outcome following frozen ET.
authors.affiliation: The Univ. of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden, Cooper Hospital/Univ. Medical Center Dept. of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Camden, USA.
authors.forename: B
authors.initials: B
authors.lastname: Katsoff
authors.forename: C
authors.initials: C
authors.lastname: Wilson
authors.forename: J H
authors.initials: JH
authors.lastname: Check
authors.forename: W
authors.initials: W
authors.lastname: Yuan
authors.forename: D
authors.initials: D
authors.lastname: Summers-Chase
mesh_terms: D000328:Adult; D015925:Cryopreservation; D004624:Embryo Transfer / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic / Q000009:adverse effects*