title: Paternal physical and sedentary activities in relation to semen quality and reproductive outcomes among couples from a fertility center.
abstract: OBJECTIVE
  Is paternal physical activity associated with semen quality parameters and with outcomes of infertility treatment?
  
  
  CONCLUSIONS
  Among men presenting for infertility treatment, weightlifting and outdoor activities were associated with higher sperm concentrations but not with greater reproductive success.
  
  
  BACKGROUND
  Higher physical activity is related to better semen quality but no studies to date have investigated whether it predicts greater reproductive success.
  
  
  METHODS
  The Environment and Reproductive Health (EARTH) Study is an on-going prospective cohort study which enrolls subfertile couples presenting at Massachusetts General Hospital (2005-2013). In total, 231 men provided 433 semen samples and 163 couples underwent 421 IVF or intrauterine insemination cycles.
  
  
  METHODS
  Leisure time spent in physical and sedentary activities over the past year was self-reported using a validated questionnaire. We used mixed models to analyze the association of physical and sedentary activities with semen quality and with clinical pregnancy and live birth rates.
  
  
  RESULTS
  Men in this cohort engaged in a median of 3.2 h/week of moderate-to-vigorous activities. Men in the highest quartile of moderate-to-vigorous activity had 43% (95% confidence interval (CI) 9, 87%) higher sperm concentrations than men in the lowest quartile (P-trend = 0.04). Men in the highest category of outdoor activity (≥1.5 h/week) and weightlifting (≥2 h/week) had 42% (95% CI 10, 84%) and 25% (95% CI -10, 74%) higher sperm concentrations, respectively, compared with men in the lowest category (0 h/week) (P-trend = 0.04 and 0.02). Conversely, men who reported bicycling ≥1.5 h/week had 34% (95% CI 4, 55%) lower sperm concentrations compared with men who reported no bicycling (P-trend = 0.05). Paternal physical and sedentary activities were not related to clinical pregnancy or live birth rates following infertility treatment.
  
  
  CONCLUSIONS
  The generalizability of the findings on live birth rates to populations not undergoing infertility treatment is limited.
  
  
  CONCLUSIONS
  Certain types of physical activity, specifically weightlifting and outdoor activities, may improve semen quality but may not lead to improved success of infertility treatments. Further research is needed in other non-clinical populations.
  
  
  BACKGROUND
  The authors are supported by NIH grants R01-ES009718, ES000002, P30-DK046200, T32-DK007703-16 and ES022955 T32-HD060454. None of the authors has any conflicts of interest to declare.
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, MA, USA Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA ajg219@mail.harvard.edu.
authors.forename: A J
authors.initials: AJ
authors.lastname: Gaskins
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, MA, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Afeiche
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: R
authors.initials: R
authors.lastname: Hauser
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA.
authors.forename: P L
authors.initials: PL
authors.lastname: Williams
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, MA, USA Department of Population Medicine, Harvard Medical School/Harvard Pilgrim Health Care Institute, Boston, MA, USA.
authors.forename: M W
authors.initials: MW
authors.lastname: Gillman
authors.affiliation: Department of Urology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: C
authors.initials: C
authors.lastname: Tanrikut
authors.affiliation: Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Petrozza
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, MA, USA Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Chavarro
mesh_terms: D000328:Adult; D001723:Birth Rate; D015444:Exercise / Q000502:physiology*; D005191:Family Characteristics; D005220:Fathers; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D057185:Sedentary Behavior; D055101:Semen Analysis; D013076:Sperm Count; D011795:Surveys and Questionnaires
keywords: assisted reproduction; male fertility; physical activity; semen quality