Biparietal diameter and menstrual age in the black population attending Edendale Hospital.

The relationship between fetal biparietal diameter measured by echography and menstrual age for blacks was studied. Predicted values and their confidence limits are presented in tables and graphs. The biparietal diameter was significantly smaller from 28 weeks than American and European studies, demonstrating that a composite graph was not applicable to the Zulus. The echographic results were checked at term by external cephalometry. Occipitofrontal circumference and birth weights for newborns were found similar to other studies. The smaller BPD in late pregnancy could be explained by the head's shape. The new charts are valuable in assessing fetal growth in African blacks.