Birth weight assessed by factor analysis.

To investigate the relevancy of birth weight, data on 300 term newborn infants were subjected to a reevaluation of 31 variables related to body measurements of both the mother and child and to the placenta. Factor analysis was introduced to analyze the data obtained. Each group was composed of multiple factor axes, of which factor structures were rather simple in Appropriate for Date (AFD) for approximating the practical images, compared to Heavy for Date (HFD) and Light for Date (LFD). In AFD, the birth weight was thought contributive by the limiting effect of the placenta, independently of the measurements of the mother. We found that the birth weight in itself seems to have a different meaning in each group, and it is difficult to readily categorize the findings on the table of equivalent parameters for labelling of the newborn.