title: HBeAg(+) and sex ratio of offspring: evidence form Taiwan's three million newborns.
abstract: OBJECTIVE
  Mothers sero-positive for hepatitis B are slightly more likely to have a son. It is not known whether it is ever having HBV (HBsAg[+]) or currently active HBV (HBeAg[+]) which is associated with having a son.
  
  
  METHODS
  Multivariable linear regression was used to assess the adjusted association of HBeAg(+) with offspring sex in all (90%) births (~3 million) in Taiwan from 1988 to 1999.
  
  
  RESULTS
  Totally, 5% of mothers were HBeAg(+). HBeAg(+) mothers were slightly more likely to have a son (sex ratio 108 rather than 106) adjusted for HBsAg, birth order, mother's age, birth year, and area of residence.
  
  
  CONCLUSIONS
  At a population level HBV status makes little difference to the sex ratio at birth.
authors.affiliation: Department of Economics, National Taiwan University, No 21, Hsu-Chow Road, Taipei, Taiwan. mjlin@ntu.edu.tw
authors.forename: Ming-Jen
authors.initials: MJ
authors.lastname: Lin
authors.forename: Pei-Jer
authors.initials: PJ
authors.lastname: Chen
authors.forename: Ming-Ching
authors.initials: MC
authors.lastname: Luoh
mesh_terms: D005260:Female; D006509:Hepatitis B / Q000453:epidemiology; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006513:Hepatitis B e Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D011247:Pregnancy; D016036:Seroepidemiologic Studies; D012744:Sex Ratio; D013624:Taiwan / Q000453:epidemiology
chemical_list: D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens