This book, the result of a working conference at the National Institute of Child Health and Human Development, is amazingly complete in its coverage of the factors known or suspected to be involved in the occurrence of premature and low-birth-weight infants. Cross-cultural influences are examined, together with those of a socioeconomic and racial nature, maternal life-styles, secular trends, events during pregnancy, prenatal care, and so on. Unfortunately, there is only passing reference to the work of Margaret and Christopher Ounsted,1 who demonstrated so nicely the influence of maternal birth weight: mothers who were born small tend to deliver smaller babies, and those born large tend to have larger babies. Their conclusion was that the constraint on birth weight is transmitted via mother.
Helen Chase reviews the recent trends. For whites, the percent of babies born small has remained at 6% to 7% since 1950. The figure for blacks and