title: Human sperm head morphometric distribution and its influence on human fertility.
abstract: OBJECTIVE
  To study the distribution of live sperm head size in semen and sperm preparations as a predictor of fertility.
  
  
  METHODS
  Prospective blind clinical trial.
  
  
  METHODS
  Academic tertiary referral center.
  
  
  METHODS
  One hundred fifty-five patients undergoing IVF treatment. Females with conditions negatively influencing fertilization were excluded.
  
  
  METHODS
  Morphometric analysis (head area, major axis, minor axis, and elongation ratio) of video images of sperm in semen and swim-up preparations used for IVF treatment was performed with a Hamilton-Thorne analyzer V 8.1 (Hamilton-Thorn Research, Beverly, MA).
  
  
  METHODS
  Oocyte fertilization.
  
  
  RESULTS
  Seventy-four percent of patients achieved fertilization. Fertilizers and nonfertilizers had different sperm head area distribution. The fertilizers had a significantly smaller interquartile range of sperm head area and of major axis in both semen and sperm preparation compared with the nonfertilizers. A subgroup of men who had fathered a child naturally had a more uniform sperm head area in semen with a significantly smaller median compared with those who failed to father a child naturally with their healthy female partner. We used multiple logistic regression applying forward stepwise selection of variables in building three predictive models of probability of fertilization.
  
  
  CONCLUSIONS
  Successful IVF or history of fathering a child was associated with a more uniform sperm head area in semen and sperm preparation.
authors.affiliation: University of Liverpool and Liverpool Women's Hospital, United Kingdom.
authors.forename: N
authors.initials: N
authors.lastname: Aziz
authors.forename: S
authors.initials: S
authors.lastname: Fear
authors.forename: C
authors.initials: C
authors.lastname: Taylor
authors.forename: C R
authors.initials: CR
authors.lastname: Kingsland
authors.forename: D I
authors.initials: DI
authors.lastname: Lewis-Jones
mesh_terms: D000328:Adult; D004311:Double-Blind Method; D004542:Ejaculation; D005260:Female; D005298:Fertility / Q000502:physiology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D011446:Prospective Studies; D012661:Semen / Q000166:cytology*; D013077:Sperm Head / Q000648:ultrastructure*; D013084:Sperm-Ovum Interactions; D018709:Statistics, Nonparametric; D014741:Video Recording