Description
Item Description:"January 1972."
"An analysis of the trend in live births registered in the United States, 1950-67 by weight at birth and period of gestation, including an assessment of the quality of the data. Other factors, such as age of mother, plurality, sex, and delivery in hospitals are included insofar as they have a bearing on the trends."
Physical Description:1 online resource (iv, 51 pages) : illustrations.
Bibliography:Includes bibliographical references (pages 30-32).