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Short, Black, Baird, Himsworth, and social class differences in fetal and neonatal mortality rates.

Since the early years of this century a series of official reports has appeared on maternal and child health, the most recent being the follow up report of the Social Services Committee published last year.' Mrs Short's committee welcomed the improvements in perinatal and neonatal mortality that had occurred since the publication of its earlier report, but like most of its predecessors, the report expressed disappointment and concern that the gradient in fetal and infant mortality rates with respect to social class remained as steep as ever2-a matter to which the Working Group on Inequalities in Health chaired by Sir Douglas Black had drawn attention four years previously.3 How, then, should we interpret and act on this apparently persistent inequality in life chances? Indeed, as mortality risks continue to fall within each of the individual social classes, should we be concerned about these inequalities at all? Social classes in Britain are derived from a classification of men s occupations. We still await the development of a satisfactory classification of women's occupations-which might be of considerable relevance to our understanding of variations in fetal and infant mortality rates.4 Be that as it may, it is the persistence of a gradient in mortality rates across the five social classes based on men's occupations that has prompted repeated expressions of concern. The persistence of social class differences in fetal and infant mortality is likely to have been influenced by three main factors: changes in the classification and distribution of occupations; selective movement of people between social classes; and persisting differences in the extent to which people of different social classes are exposed to various environmental determinants of mortality risks, including social and medical care.' Firstly, to what extent might the persisting gradient reflect changing features of the occupational classification? The origin of the classification is usually associated with the name of T H C Stevenson, superintendent of statistics at the General Register Office at the beginning of this century. There is some dispute about his reasons for developing the classification,66 but he maintained that it was intended to reflect differences in both wealth and culture between groups of individuals.9 He believed these to be important determinants of mortality risks, a belief that was very reasonable given the evidence which had accumulated during the sanitary revolution that environmental factors were important in this respect.