The relationship of ponderal index and other measurements to birthweight in preterm neonates.

The objective was to determine the relationship between birthweight and anthropometric indices (PI and MAC/ OFC) in preterm infants. A group of 163 singleton preterm neonates born at 24-36 weeks were examined. Measurements were made of crown-heel length, midarm circumference, and occipito-frontal circumference. Birthweights were calculated as multiples of the mean (MoMs) for a given stage of gestation. There was a highly significant correlation between gestational age and MAC/OFC (p < 0.0001) but none with ponderal index. There was a significant correlation between weight expressed as multiples of the mean and both ponderal index (p < 0.008) and MAC/OFC (p < 0.0001). This relationship between birthweight and anthropometric indices suggests that measurement of the ponderal index does not provide a useful index of intrauterine nutrition.