title: Polynuclear fertilization in various stimulation protocols in in vitro fertilization.
abstract: OBJECTIVE
  To investigate the effect of some clinical characteristics, especially various ovarian stimulation protocols, on the occurrence of polypronuclear fertilization.
  
  
  METHODS
  One hundred forty-eight consecutive cycles in 121 patients were treated in our IVF program and 735 oocytes were analyzed retrospectively.
  
  
  RESULTS
  Multipronuclear fertilization occurred in 33 of 530 fertilized oocytes, an incidence of 6.2%. No significant difference in the incidence of polyploidy was observed between the three stimulation protocols (CC/hMG, hMG, GnRHa/hMG). Number of polypronuclear embryos was found to be correlated with the fertilization rate, concentration of sperm inseminated, and maturity of the oocytes.
  
  
  CONCLUSIONS
  The maturity of the oocytes and the sperm fertilizing capacity should be examined to reduce the incidence of polypronuclear fertilization.
authors.affiliation: Department of Obstetrics and Gynecology, Asahikawa Medical College, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sengoku
authors.forename: M
authors.initials: M
authors.lastname: Ishikawa
authors.forename: K
authors.initials: K
authors.lastname: Tamate
authors.forename: T
authors.initials: T
authors.lastname: Shimizu
mesh_terms: D002996:Clomiphene / Q000627:therapeutic use; D005260:Female; D005307:Fertilization in Vitro; D007987:Gonadotropin-Releasing Hormone / Q000627:therapeutic use; D006801:Humans; D007246:Infertility / Q000628:therapy; D008297:Male; D008596:Menotropins / Q000627:therapeutic use; D010062:Ovulation Induction; D011003:Ploidies; D012189:Retrospective Studies; D013076:Sperm Count; D013081:Sperm Motility
chemical_list: D002996:Clomiphene; D007987:Gonadotropin-Releasing Hormone; D008596:Menotropins