The association of maternal social class with maternal diet and the dimensions of babies in a population of London women.

Records of the diets of 513 London mothers towards the end of the first trimester of pregnancy have been reported previously to show the maternal nutritional intakes associated with birthweight in the optimum range, which may be assumed to approximate to basic maternal needs for reproduction. The diets associated with low birthweight and small head size were also recorded and were found to be inferior. The present paper shows social class gradients for baby size and 35 essential dietary components, providing an indication of which basic maternal nutritional needs were not always met. There was no social class gradient for intake of total energy, or the energy carriers carbohydrate and fat. There were, however, statistically highly significant social class gradients for intake of protein, seven minerals and six B-vitamins, all of which were also highly significantly correlated with birthweight. Maternal intake of these 14 components of diet fell progressively as birthweight fell, but only for the mothers of smaller babies below 3270g, the median for the study. Further increase of maternal intakes of any nutrient by mothers whose babies were above median did not apparently further increase birthweight. The social and medical problem presented by maternal nutrition is that of a minority of women who enter pregnancy with qualitatively inadequate nutritional status. This minority is found in all social classes but increases from social class I to V, and further still among single mothers. The women comprising this minority eat foods not meeting basic maternal needs for a range of nutrients characteristic of whole grains, vegetables and fruit and dairy produce, which may partly be explained by their high cost.