title: The correlation between sperm cell morphology and fertilization after zona pellucida slitting in subfertile males.
abstract: OBJECTIVE
  This work was undertaken to evaluate the correlation between sperm cell morphology and fertilization after zona pellucida slitting in subfertile males.
  
  
  METHODS
  Twenty-two couples who failed at least one in vitro fertilization attempt because of lack of oocytes fertilization underwent a zona-slitting micromanipulative procedure. A total of 245 oocytes were retrieved and inseminated by three different modes: 151 oocytes underwent micromanipulation, 2 were damaged, and the remaining 149 inseminated by the husband's sperm (group A). Fifty-five oocytes were not manipulated and inseminated by the husband's sperm (group B), and 39 oocytes were not manipulated and inseminated by a donor sperm (group C).
  
  
  RESULTS
  Fertilization rates were 26.8%, 5.5%, and 53.8% in groups A, B, and C, respectively, and differed significantly between group A and group B. The cleavage rates were lower for oocytes fertilized by the husband's sperm (48.6%) than that obtained by donor (90%), suggesting a sperm factor contributing to this phenomenon. The procedure was most efficient in patients with a total motile sperm count after preparation of greater than or equal to 5 million and with either normal sperm morphology or defects localized to the acrosome or tail region only. Sperm with nuclear morphological abnormalities demonstrated a marked reduction in fertilization potential.
  
  
  CONCLUSIONS
  It is concluded that the zona-slitting technique enhances fertilization of severely subfertile sperm, and its efficacy is affected by sperm morphology and a threshold concentration of motile cells.
authors.affiliation: Department of Obstetrics and Gynecology, Hadassah University Hospital, Jerusalem, Israel.
authors.forename: A
authors.initials: A
authors.lastname: Simon
authors.forename: J
authors.initials: J
authors.lastname: Younis
authors.forename: A
authors.initials: A
authors.lastname: Lewin
authors.forename: B
authors.initials: B
authors.lastname: Bartoov
authors.forename: J G
authors.initials: JG
authors.lastname: Schenker
authors.forename: N
authors.initials: N
authors.lastname: Laufer
mesh_terms: D000818:Animals; D002970:Cleavage Stage, Ovum; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D007248:Infertility, Male / Q000628:therapy*; D008297:Male; D011247:Pregnancy; D013076:Sperm Count; D013081:Sperm Motility; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000166:cytology* / Q000502:physiology; D015044:Zona Pellucida / Q000502:physiology* / Q000648:ultrastructure