title: Frequency of defective sperm-zona pellucida interaction in severely teratozoospermic infertile men.
abstract: BACKGROUND
  The frequency of defective sperm-zona pellucida (ZP) interaction in teratozoospermic infertile men was investigated.
  
  
  METHODS
  Sperm-ZP binding and the ZP-induced acrosome reaction (ZPIAR) were performed in 125 infertile men with <5% of their sperm with normal morphology (strict criteria), but with a sperm count > or =20x10(6)/ml and total motility >30% in semen. Oocytes that failed to fertilize in clinical IVF were used for the tests. Four oocytes were incubated for 2 h with 2x10(6)/ml motile sperm selected by swim-up. The number of sperm bound per ZP and ZPIAR were assessed. Under these conditions, an average < or sperm bound per ZP was defined as poor sperm-ZP binding, and a ZPIAR < or = was defined as low ZPIAR.
  
  
  RESULTS
  Among 125 teratozoospermic men, 31% (39/125) had poor sperm-ZP binding. Of those without poor ZP binding, 48% (41/86) had low ZPIAR. Some 64% (28/44) with sperm counts between 20 and 60x10(6)/ml had low ZPIAR. Only 36% (45/125) had normal sperm-ZP binding and ZPIAR.
  
  
  CONCLUSIONS
  Defective sperm-ZP interaction was present in 64% of teratozoospermic infertile men: 31% had defective sperm-ZP binding, and 33% low ZPIAR. The frequency of low ZPIAR was higher in men with sperm counts between 20-60x10(6)/ml.
authors.affiliation: University of Melbourne Department of Obstetrics and Gynaecology, Reproductive Services, Royal Women's Hospital and Melbourne IVF, Victoria 3035, Australia. dyl@unimelb.edu.au
authors.forename: De Yi
authors.initials: DY
authors.lastname: Liu
authors.forename: H W Gordon
authors.initials: HW
authors.lastname: Baker
mesh_terms: D020101:Acrosome Reaction; D005260:Female; D006801:Humans; D007248:Infertility, Male / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D012720:Severity of Illness Index; D013076:Sperm Count; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000002:abnormalities* / Q000502:physiology*; D015044:Zona Pellucida / Q000502:physiology