title: Comparison of the frequency of defective sperm-zona pellucida (ZP) binding and the ZP-induced acrosome reaction between subfertile men with normal and abnormal semen.
abstract: BACKGROUND
  The aim of this study was to compare the frequency of defective sperm-zona pellucida (ZP) binding (DSZPB) and defective ZP-induced acrosome reaction (DZPIAR) in subfertile men (i.e. male partners of infertile couples) with normal and abnormal semen analyses.
  
  
  METHODS
  A total of 1030 subfertile men with normal semen analysis (n=255), oligozoospermia (count<20x10(6)/ml, n=136), severe teratozoospermia (strict normal morphology<or=5%, n=294) and mild-moderate teratozoospermia (morphology 6-14%, n=345) were studied. Unfertilized oocytes from clinical in vitro fertilization/intracytoplasmic sperm injection were used for sperm-ZP interaction tests. After 2 h incubation of motile sperm with four oocytes, sperm tightly bound to the ZP, and the AR of ZP-bound sperm (ZPIAR) were assessed. An average of <40 sperm bound/ZP and <16% ZPIAR were used for diagnosis of DSZPB or DZPIAR.
  
  
  RESULTS
  For the groups of men with normal semen or mild-moderate teratozoospermia, severe teratozoospermia and oligozoospermia, the frequencies of DSZPB were: 13, 21, 29 and 28%, respectively, and in those normal SZPB, DZPIAR were 27, 36, 56 and 68%, respectively. Overall DSZPB and ZPIAR were 36, 49, 68 and 77% for the four groups, respectively. The highest frequencies of defective sperm-ZP interaction were in the oligozoospermia and severe teratozoospermia groups. In the normal and teratozoospermia groups, subjects with a relatively low sperm concentration (20-60x10(6)/ml) had a significantly higher frequency of DZPIAR.
  
  
  CONCLUSIONS
  Defective sperm-ZP interaction is a major mechanism of male infertility. DZPIAR is more frequent than DSZPB in subfertile men with either normal or abnormal semen, suggesting that sequential sperm-ZP interaction tests are essential to detect these sperm defects.
authors: Department of Obstetrics and Gynaecology, University of Melbourne, Royal Women's Hospital, 132, Grattan Street, Carlton, Victoria 3053, Australia. dyl@unimelb.edu.au
authors: De Yi
authors: DY
authors: Liu
authors: Ming Li
authors: ML
authors: Liu
authors: Claire
authors: C
authors: Garrett
authors: H W Gordon
authors: HW
authors: Baker
mesh_terms: D020101:Acrosome Reaction; D005260:Female; D006801:Humans; D007248:Infertility, Male; D008297:Male; D009845:Oligospermia / Q000175:diagnosis*; D009865:Oocytes / Q000378:metabolism; D011485:Protein Binding; D012661:Semen / Q000378:metabolism*; D013076:Sperm Count; D013081:Sperm Motility; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000378:metabolism* / Q000473:pathology; D015044:Zona Pellucida / Q000378:metabolism*