Biologic bases for international fetal growth curves.

A simple, inexpensive method for assessing maternal nutritional status during pregnancy was sought to control for nutrition in the development of fetal growth curves for diverse populations. Triceps skinfold thickness was measured at intervals throughout pregnancy in 60 Ethiopian women. In normally nourished pregnancies this measurement increases in the first two trimesters and decreases in the third, reflecting early pregnancy storage of fat and its release in late gestation to meet the increasing energy needs of the fetus. Ethiopian women who had skinfold thickness increases and decreases as great as those in the United Kingdom (UK) had neonates as heavy as those in the UK. This may mean that Ethiopian fetuses have the same growth potential as those in the UK and that the same growth curves can be used for the two populations. Skinfold thickness measurements may be the means by which nutrition can be controlled as a growth factor in determining the intrinsic fetal growth potentials of diverse populations.