title: Body mass index in relation to semen quality, sperm DNA integrity, and serum reproductive hormone levels among men attending an infertility clinic.
abstract: OBJECTIVE
  To examine the association between body weight and measures of male reproductive potential.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Fertility clinic in an academic medical center.
  
  
  METHODS
  Four hundred eighty-three male partners of subfertile couples.
  
  
  METHODS
  None.
  
  
  METHODS
  Standard semen analysis, sperm DNA fragmentation, and serum levels of reproductive hormones.
  
  
  RESULTS
  As expected, body mass index (BMI) was positively related to estradiol levels and inversely related to total testosterone and sex hormone-binding glogulin (SHBG) levels. There was also a strong inverse relation between BMI and inhibin B levels and a lower testosterone:LH ratio among men with a BMI > or = 35 kg/m(2). Body mass index was unrelated to sperm concentration, motility, or morphology. Ejaculate volume decreased steadily with increasing BMI levels. Further, men with BMI > or = 35 kg/m(2) had a lower total sperm count (concentration x volume) than normal weight men (adjusted difference in the median [95% confidence interval] = -86 x 10(6) sperm [-134, -37]). Sperm with high DNA damage were significantly more numerous in obese men than in normal-weight men.
  
  
  CONCLUSIONS
  These data suggest that despite major differences in reproductive hormone levels with increasing body weight, only extreme levels of obesity may negatively influence male reproductive potential.
authors.affiliation: Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA. jchavarr@hsph.harvard.edu
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Chavarro
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Toth
authors.forename: Diane L
authors.initials: DL
authors.lastname: Wright
authors.forename: John D
authors.initials: JD
authors.lastname: Meeker
authors.forename: Russ
authors.initials: R
authors.lastname: Hauser
mesh_terms: D000328:Adult; D000554:Ambulatory Care Facilities; D015992:Body Mass Index; D053938:DNA Fragmentation; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D007248:Infertility, Male / Q000097:blood* / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology; D008019:Life Style; D008297:Male; D009765:Obesity / Q000097:blood / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology; D012661:Semen / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D055101:Semen Analysis; D012738:Sex Hormone-Binding Globulin / Q000032:analysis
chemical_list: D012739:Gonadal Steroid Hormones; D012738:Sex Hormone-Binding Globulin