title: Effect of fertilization by intracytoplasmic sperm injection versus conventional insemination on embryo cleavage rates.
abstract: OBJECTIVE
  To determine if fertilization by conventional oocyte insemination vs intracytoplasmic sperm injection (ICSI) causes any difference in the maximum number of blastomeres of fresh or frozen thawed embryos transferred.
  
  
  METHODS
  Retrospective evaluation of all in vitro fertilization (IVF) cycles over a 10-year period in cycles having a 2 embryos transferred where the semen analysis was normal except for strict morphology which was allowed to be 2-5% normal. The percentage of the maximum number of blastomeres in any transfers was compared according to the method of insemination.
  
  
  RESULTS
  There were no differences in the maximum blastomere numbers in cycles where there was conventional insemination vs ICSI.
  
  
  CONCLUSIONS
  Though higher pregnancy rates have been found following the transfer of embryos derived from conventional oocyte insemination vs ICSI, and higher pregnancy rates were found following single embryo day 3 transfers with embryos with more blastomeres, the beneficial effect of conventional insemination does not seem to be related to forming embryos with more rapid cleavage.
authors.affiliation: The University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden, Cooper Hospital/University Medical Center, Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology & Infertility, Camden, NJ, USA. laurie@ccivf.com
authors.forename: J H
authors.initials: JH
authors.lastname: Check
authors.forename: A
authors.initials: A
authors.lastname: Bollendorf
authors.forename: E
authors.initials: E
authors.lastname: Dix
authors.forename: D
authors.initials: D
authors.lastname: Katsoff
mesh_terms: D001757:Blastomeres; D002970:Cleavage Stage, Ovum; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic