title: Seasonality updated in 28 European/Mediterranean countries: A continuing enigma.
abstract: OBJECTIVE
  This report updates birth seasonality for 28 European/Mediterranean countries and evaluates the possible influence of atmospheric clarity/quality on seasonality.
  
  
  METHODS
  Birth data between 1970 and 2011 were adjusted for seasonality and are presented as conceptions.
  
  
  RESULTS
  Presently, 27 of 28 countries have peak conceptions during the last 3 months of the year, a greater concentration than was previously recognized.
  
  
  CONCLUSIONS
  There is no apparent explanation for the en masse transition of seasonality, particularly the abrupt change in seasonality for nine countries, The frequency of sexual intercourse might be a one determinant while another possibility might be the decadal changes in atmospheric clearness/quality. However, causal relationships cannot be inferred without further study and/or animal experimentation.
authors.affiliation: 612 5th Street NE, Dilworth, Minnesota, 56529.
authors.forename: David R
authors.initials: DR
authors.lastname: Cummings
mesh_terms: D000352:Africa, Northern; D005060:Europe; D005306:Fertilization; D006801:Humans; D036801:Parturition; D012621:Seasons; D013997:Time Factors