The scope of perinatal statistics and the usefulness of international comparisons.
D003431:Cross-Cultural Comparison; D005260:Female; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008423:Maternal Age; D011247:Pregnancy; D012923:Social Class; D006113:United Kingdom; D014944:World Health Organization