title: Evidence of economic deprivation and female foeticide in a United Nations global births by gender data set.
abstract: BACKGROUND
  The male-to-female ratio of live births is expressed as the ratio of male births divided by total births (M/F). Males are produced approximately 3% in excess. A large number of factors have been found to influence M/F. Stress and privation reduces M/F. Gender preference (which almost invariably favours males) with selective female foetal abortion increases M/F. This study was carried out in order to assess a United Nations data set for evidence of global trends in M/F in relation to broad socioeconomic conditions and male preference.
  
  
  METHODS
  Data (M/F and total births, 1955-2009) was obtained from the United Nations (UN) Department of Economic and Social Affairs, Population Division, Population Estimates and Projection Section. The following regions were analysed: more developed countries, less developed countries and least developed countries (as defined by the UN General Assembly).
  
  
  RESULTS
  More developed countries: M/F was initially stable at 0.53 up to 1979 then fell to 0.525. Less developed countries: M/F was initially stable at 0.53 then rose after 1984 to 0.545 with a rise in male births and a fall in female births (estimated female birth deficit=48734993). Least developed countries: exhibited a stable M/F of 0.52 (all p<<0.001).
  
  
  CONCLUSIONS
  This study has confirmed, on a global scale, that least developed countries have the lowest M/F. The rise in M/F in developed countries (which includes Asia) confirms widespread selective female foeticide due to cultural male preference. The declining trend in M/F in developed countries has been previously noted and remains unexplained.
authors.affiliation: Academic Department of Paediatrics, Medical School, Mater Dei Hospital, Malta. Electronic address: victor.e.grech@gov.mt.
authors.forename: Victor
authors.initials: V
authors.lastname: Grech
mesh_terms: D000028:Abortion, Induced; D001723:Birth Rate; D003906:Developing Countries; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011203:Poverty; D011247:Pregnancy; D012744:Sex Ratio; D014480:United Nations
keywords: Birth rate/*trends; Economics; Infant; Newborn; Psychological/physiopathology; Sex ratio; Stress