Noninvasive characterization of neonatal adipose tissue by 13 C magnetic resonance spectroscopy

Abstract In vivo 13 C magnetic resonance spectroscopy (MRS) was applied noninvasively to analyze the fatty acid composition of adipose tissue in 21 full‐term newborn infants and 6 mothers. In order to assess the effects of gestational and postnatal age on adipose tissue composition, we studied preterm infants at birth, term infants at the ages of 6 wk and at 6 mon. We also investigated the influence of maternal diet on infant adipose tissue composition by studying the breast‐fed infants of women who maintained either an omnivore or a vegan diet. Significant differences were observed in adipose tissue composition of neonates compared with their mothers. Neonates had more saturated and less unsaturated fatty acids than their mothers ( P <0.01). We also observed changes in adipose tissue composition with maturity. From birth to 6 wk of age 13 C MR spectra showed a significant increase in the amount of unsaturated fatty acids, particularly polyunsaturated fatty acids ( P <0.01). Similarly, differences were seen as a result of gestational age. Preterm infants had relatively fewer unsaturated fatty acids than full‐term infants. A greater proportion of these unsaturated fatty acids were polyunsaturated. Our results demonstrate that 13 C MRS can be utilized to assess noninvasively neonatal adipose tissue lipid composition and to monitor the effects of developmental changes due to gestational age and oral feeding.