Preterm infants inevitably accumulate a significant nutrient deficit in the first few weeks of life that will not be replaced when current RDIs are fed. This deficit can be directly related to subsequent postnatal growth retardation.postnatal growth retardation, preterm infants.

Diets deficient in the w-6 fatty acid linoleic acid reduce arachidonic acid (Ach) concentrations and retard growth of developing animals and humans. Nevertheless, plasma phosphatidylcholine Ach concentrations declined from 84 ± 23 mg/liter at birth to a nadir of 38 ± 11 mg/liter at 4 mo of age in preterm infants fed commercial formulas with linoleic acid, and weight normalized to that of term infants fell progressively beginning at 2 mo of age. The nadir of plasma phosphatidylcholine Ach (31 ± 7 mg/liter) and growth were further reduced by formula containing marine oil compared with the commercial formulas. Ach status (defined as the mean plasma phosphatidylcholne Ach concentration at 2, 4, and 6.5 mo) correlated with one or more measures of normalized growth through 12 mo. Ach status and maternal height accounted for as much as 59% of the weight variance and 68% of the length variance in infants fed standard formulas. Better Ach status was not from higher energy intakes. A conditional Ach deficiency in preterm infants may contribute to growth over the first year of life. On the strength of the relationship between Ach status and growth, we hypothesize that dietary Ach could improve first year growth of preterm infants.Despite recent advances in neonatal intensive care, preterm infants do not achieve first year growth equivalent to that of infants born at term (1-5). Moreover, preterm infants remain smaller than term infants after the first year of life (6, 7), and poorer individual growth is associated with poorer mental and motor performance (8)(9)(10)(11). That infants with chronic lung disease have poorer growth after discharge is well known (12-14); however, preterm infants free of chronic illness and fed standard formulas had progressive declines in normalized weight, weight-to-length ratio, and head circumference beginning 2 mo after expected delivery (15), as has been reported (1,3).Erythrocyte phospholipid arachidonic acid (Ach) in these infants also fell progressively, reaching a nadir 4 mo after expected term delivery (16) below that seen in formula-fed term infants of equivalent age (17). The nadir in plasma phospholipid Ach concentration coincided with the onset of the decline in normalized weight. The mean concentration of Ach in plasma phosphatidylcholine (PtdCho) of preterm infants at birth is 84 ± 23 mg/liter (mean ± SD, range 43-152, n = 86, unpublished data). When these infants were 3 weeks old, this value was 67 mg/liter (range 41-136 mg/liter, n = 59), and by 4 mo after term this value was 38 ± 11 mg/liter (n = 29). Direct evidence that normalized growth might relate to Ach status came from the observation that marine oilsupplemented formula further decreased the concentrations of plasma PtdCho Ach (31 ± 7 mg/liter) (16) and normalized weights (15) compared with standard formula. Plasma PtdCho linoleic acid (Lin) concentration remained high and was unaffected by marine oil supplementation.Diets deficient in the essential w6 fatty acid, Lin, cause declines in phospholipid Ach (18) and...

Very low birth weight (VLBW) infants (748-1390 g, n = 65) were randomly assigned to receive control or marine oil-supplemented formula when they achieved intakes > 454 kJ (110 kcal)/kg/d of a formula designed for VLBW infants. Study formulas with or without marine oil were provided until 79 wk of postconceptional age (PCA), first in a formula designed for preterm infants followed by a formula designed for term infants. Infants were studied at regular intervals through 92 wk PCA. Weight, length, and head circumference were determined by standardized procedures and normalized to the National Center for Health Statistics figures for growth of infants born at term of the same age and gender. Mean normalized weight, weight-to-length, and head circumference were greatest at 48 wk and decreased thereafter. The decline in normalized weight was greater in infants fed the marine oil-supplemented formula. Beginning at 40 wk, marine oil-supplemented infants compared to controls had significantly poorer Z-scores for weight, length and head circumference. In addition, birth order (negatively) and maternal height (positively) influenced weight and length achievement in infancy as shown previously in infants born at term.

Background: Previous data from this unit suggest that postnatal growth retardation (PGR) is inevitable in preterm infants. However, the study was performed in a single level III neonatal intensive care unit and applicability of the findings to other level III or level I-II special care baby units was uncertain. Objectives: To examine postnatal hospital growth and to compare growth outcome in preterm infants discharged from four level III tertiary care units and 10 level I-II special care baby units in the former Northern Region of the United Kingdom. Subjects/methods: Preterm infants (( 32 weeks gestation; ( 1500 g) surviving to discharge were studied. Infants were weighed at birth and discharge. Body weight was converted into a z score using the British Foundation Growth Standards. To ascertain the degree of PGR, the z score at birth was subtracted from the z score at discharge. Data were evaluated using a combination of split plot (level III v I-II = main factor; individual centre = subfactor) and stepwise regression analyses. Results were considered significant at p , 0.05. Results: A total of 659 (level III, n = 335; level I-II, n = 324) infants were admitted over a 24 month period (January 1998-December 1999. No differences were detected in birth characteristics, CRIB score (a measure of illness in the first 24 hours of life), length of hospital stay, weight gain, weight at discharge, or degree of PGR between infants discharged from level III and level I-II units. Significant variation was noted in length of hospital stay (,35%; p , 0.001), weight gain (,33%; p , 0.001), weight at discharge (,20%; p , 0.001), and degree of PGR (,200%; p , 0.001) between the level III units. Even greater variability was noted in the duration of hospital stay (,40%; p , 0.001), weight gain (,60%; p , 0.001), weight at discharge (,40%, p , 0.001), and degree of PGR (,300%, p , 0.001) between the level I-II units. Conclusions: These data stress the variable but universal nature of PGR in preterm infants discharged from level III and I-II neonatal intensive care units and raise important questions about nutritional support of these infants before and after hospital discharge.