title: Urinary Phytoestrogens Are Associated with Subtle Indicators of Semen Quality among Male Partners of Couples Desiring Pregnancy.
abstract: BACKGROUND
  Phytoestrogens have been associated with subtle hormonal changes, although effects on male fecundity are largely unknown.
  
  
  OBJECTIVE
  We evaluated associations between male urinary phytoestrogen (isoflavone and lignan) concentrations and semen quality.
  
  
  METHODS
  This study was a prospective cohort study of 501 male partners of couples desiring pregnancy and discontinuing contraception. Each participant provided up to 2 semen samples that were analyzed for 35 semen quality endpoints the following day. Linear mixed-effects models were used to estimate associations between baseline urinary phytoestrogen concentrations and semen quality parameters, adjusted for age, body mass index (BMI), research site, and serum lipid and cotinine concentrations.
  
  
  RESULTS
  Most associations between urinary phytoestrogens and semen quality parameters were null. However, select individual phytoestrogens were associated with semen quality parameters, with associations dependent on the class of phytoestrogens and modified by BMI. Specifically, genistein and daidzein were associated with a lower percentage of normal sperm and increased abnormalities in semen morphology, with reduced associations observed as BMI increased (P < 0.05) [percentages (95% CIs) of normal morphology by WHO traditional criteria: genistein, main effect: -5.61% (-9.42%, -1.79%); interaction: 0.19% (0.06%, 0.31%) per log unit increase; daidzein, main effect: -5.35% (-9.36%, -1.34%); interaction: 0.18% (0.05%, 0.32%) per log unit increase]. Enterolactone was associated with fewer abnormalities in semen morphometry and morphology and decreased DNA fragmentation, with reduced associations observed as BMI increased (P < 0.05) [percentages (95% CIs) of abnormalities in the neck and midpiece: enterolactone, main effect: -3.35% (-6.51%, -0.19%); interaction: 0.11% (0.01%, 0.21%) per log unit increase].
  
  
  CONCLUSIONS
  These results suggest that male urinary phytoestrogen concentrations characteristic of the US population may be associated with subtle indicators of male fecundity and semen quality but were not associated with couple fecundity.
authors.affiliation: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Department of Health and Human Services, Bethesda, MD; and mumfords@mail.nih.gov.
authors.forename: Sunni L
authors.initials: SL
authors.lastname: Mumford
authors.affiliation: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Department of Health and Human Services, Bethesda, MD; and.
authors.forename: Sungduk
authors.initials: S
authors.lastname: Kim
authors.affiliation: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Department of Health and Human Services, Bethesda, MD; and.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Rollins School of Public Health, Emory University, Atlanta, GA.
authors.forename: Dana
authors.initials: D
authors.lastname: Boyd Barr
authors.affiliation: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Department of Health and Human Services, Bethesda, MD; and.
authors.forename: Germaine M
authors.initials: GM
authors.lastname: Buck Louis
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives / Q000652:urine; D000328:Adult; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003367:Cotinine / Q000097:blood; D053938:DNA Fragmentation; D023381:Endpoint Determination; D005260:Female; D005298:Fertility / Q000502:physiology; D019833:Genistein / Q000652:urine; D006801:Humans; D007529:Isoflavones / Q000652:urine; D017705:Lignans / Q000652:urine; D016014:Linear Models; D008297:Male; D048789:Phytoestrogens / Q000652:urine*; D011247:Pregnancy; D011446:Prospective Studies; D055101:Semen Analysis / Q000379:methods*
chemical_list: D007529:Isoflavones; D017705:Lignans; D048789:Phytoestrogens; C004742:daidzein; D002784:Cholesterol; D019833:Genistein; D003367:Cotinine; D015107:4-Butyrolactone; C029497:2,3-bis(3'-hydroxybenzyl)butyrolactone
keywords: isoflavones; lignans; male fertility; phytoestrogens; semen quality