title: Preconception stress and the secondary sex ratio in a population-based preconception cohort.
abstract: OBJECTIVE
  To examine the association between preconception parental stress and the secondary sex ratio, defined as the ratio of males to females at birth.
  
  
  METHODS
  A population-based preconception cohort.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  A total of 235 couples who were enrolled before conception in Michigan and Texas between 2005 and 2009 and who had a singleton birth during the follow-up period. Couples were interviewed separately at baseline to obtain information on perceived stress (Cohen's Perceived Stress Scale) and lifetime history of physician-diagnosed anxiety and/or mood disorders. Female partners were also trained to collect basal saliva samples for the measurement of salivary stress markers, alpha-amylase and cortisol.
  
  
  METHODS
  None.
  
  
  METHODS
  Birth outcome data including infant sex were collected upon delivery. Modified Poisson regression models were used to estimate the relative risks (RRs) of a male birth for each stress marker.
  
  
  RESULTS
  After adjusting for potential confounders, we observed a 76% increase in the risk of fathering a male infant (RR 1.76; 95% confidence interval 1.17-2.65) in men diagnosed with anxiety disorders compared with those who were not diagnosed. When lifetime history of physician-diagnosed anxiety disorders was modeled jointly for the couple, the association was slightly strengthened (RR 2.03; 95% confidence interval 1.46-2.84).
  
  
  CONCLUSIONS
  This prospective cohort study suggests that paternal lifetime history of physician-diagnosed anxiety disorders may be associated with an increase in the secondary sex ratio, resulting in an excess of male births.
authors.affiliation: Department of Preventive Medicine, Catholic University of Daegu School of Medicine, Daegu, South Korea; Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland. Electronic address: jialove@cu.ac.kr.
authors.forename: Jisuk
authors.initials: J
authors.lastname: Bae
authors.affiliation: Department of Obstetrics and Gynecology, The Ohio State University College of Medicine, Columbus, Ohio.
authors.forename: Courtney D
authors.initials: CD
authors.lastname: Lynch
authors.affiliation: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland.
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, Bethesda, Maryland.
authors.forename: Rajeshwari
authors.initials: R
authors.lastname: Sundaram
authors.affiliation: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland.
authors.forename: Katherine J
authors.initials: KJ
authors.lastname: Sapra
authors.affiliation: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland.
authors.forename: Germaine M
authors.initials: GM
authors.lastname: Buck Louis
mesh_terms: D000328:Adult; D001007:Anxiety / Q000175:diagnosis / Q000453:epidemiology* / Q000378:metabolism / Q000523:psychology; D015415:Biomarkers / Q000378:metabolism; D005220:Fathers / Q000523:psychology*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D050498:Live Birth; D008137:Longitudinal Studies; D008297:Male; D008824:Michigan / Q000453:epidemiology; D009035:Mothers / Q000523:psychology; D016017:Odds Ratio; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D012307:Risk Factors; D012463:Saliva / Q000378:metabolism; D012744:Sex Ratio; D013315:Stress, Psychological / Q000175:diagnosis / Q000453:epidemiology* / Q000378:metabolism / Q000523:psychology; D013781:Texas / Q000453:epidemiology; D013997:Time Factors; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D015415:Biomarkers; D000516:alpha-Amylases; D006854:Hydrocortisone
keywords: Alpha-amylases; anxiety disorders; hydrocortisone; sex ratio; stress