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Growth outcome for 1 year of corrected age and feeding practices during that first year of life were described for a large population of very low birth weight (VLBW) infants. Growth patterns of weight, length, and occipitofrontal circumference through 12 months of corrected age, and weight/length ratios at 12 months, were determined for 122 VLBW infants less than or equal to 1500 gm and less than or equal to 35 weeks of gestational age at birth; feeding practices were surveyed within a subpopulation of 89 infants. Differences in growth were apparent when infants were grouped according to sex and appropriateness of intrauterine growth. When the mean values of each group were compared, the female infants of appropriate size for gestational age demonstrated growth at higher percentiles (National Center for Health Statistics term-infant norms) for all three measurements (weight, length, and occipitofrontal circumference). Male infants whose size was appropriate for gestational age, and male and female infants who were small for gestational age, all grew similarly, at lower percentiles for weight and length, when compared with the same norms. Growth in occipitofrontal circumference was closest to term infant norms in all subgroups of infants. The majority of the infants, regardless of subgroup, achieved weights and lengths greater than 5th percentile and proportionate growth with a normal weight/length ratio. At 12 months of corrected age, 30% remained at less than 5th percentile in weight, 21% in length, and 14% in occipitofrontal circumference. Eighteen infants (15%) had a marked discrepancy in weight for length, with a weight/length ratio less than 5th percentile. Three prevalent practices that could result in compromised nutrition were identified: (1) cereals were introduced at an early age, (2) 2% and skim cow milk were fed to approximately 50% of the infants within the first year of life, and (3) whole cow milk was introduced to some VLBW infants at an early age. Caretakers apparently viewed their infants in terms of chronologic age rather than age corrected for prematurity when it came to the initiation of solids and cow milk. Whether increased attention to appropriate feeding practices during the first year of life would result in a more favorable growth outcome for VLBW infants is not known.

Lactobezoars have been reported with increasing frequency in low-birth-weight infants. The etiology of a lactobezoar is not well understood and is probably multifactorial. During a 2 1/2-year period, 29 of 442 infants weighing less than 2,000 g who were fed casein-predominant formulas had lactobezoars. During the subsequent 14-month period, 223 infants weighing less than 2,000 g were fed a whey-predominant formula, and none had lactobazoars. There have been no reports of lactobezoars in infants fed human milk or whey-predominant formulas. It would appear that the presence of casein as the predominant protein is necessary for the development of a lactobezoar.

New methods of feeding low-birth-weight infants have been developed as a result of improved knowledge concerning the nutritional requirements of the premature infant. Breast milk may offer certain nutritional and non-nutritional advantages for immature babies. Preterm milk is theoretically more appropriate than term or pooled mature breast milk. However, some nutrients may be inadequate to support intrauterine rates of growth in small premature infants. New formulas specifically designed for preterm babies appear to be safe and to promote improved weight gain, fat absorption, bone mineralization, and nitrogen retention. Nutritional needs of growing preterm infants are better met by preamture formulas than by formulas designed for term babies.

The reported energy content of infant formulas will vary, depending upon the method used to calculate or measure the caloric value. Manufacturers' specifications regarding the energy content of milk formulas reflects the 'metabolizable' energy. i.e., the amount of energy which is digested and absorbed by the infant. However, estimates of absorptive efficiency are based primarily upon studies in young adult subjects fed mixed diets and therefore may not be generally applicable to all neonates. The actual caloric content of formulas may be determined accurately by bomb calorimetry which is not influenced by the relative metabolic efficiency of the infant who may utilize the formula. Therefore, it may be preferable to express the caloric value of milk base formulas in terms of absolute combustible energy.

Fifteen low birth weight infants had their conditions complicated by the formation of a lactobezoar. The mean gestational age was 30.3 weeks; mean birth weight was 1,184 g, and the mean age at the time of diagnosis was 11.8 days. Twelve of the infants were receiving an 80 kcal/dL-formula and one infant, a 40 kcal/dL-formula designed for the premature infant. Symptoms included abdominal distension, emesis or increased gastric residual, diarrhea, hematest-positive stools, abdominal mass, and gastric perforation.

The present study was undertaken to determine both the time at which exponential growth of bacteria ensued in human milk during a continuous feeding and whether the fat content of the milk changed during a continuous feeding. Breast milk samples were obtained from 19 healthy lactating women between the 7th and 28th postpartum day. Nine samples were refrigerated and utilized in a simulated continuous feeding within 24 hours of collection. The remaining 10 samples were frozen for four to six weeks until use in the simulated feeding study. Bacterial colony counts and fat content (by creamatocrit) were then measured at the beginning of the simulated feeding and at hourly intervals from five to eight hours after the initiation of the study. Results indicated that logarithmic growth of the contaminating bacteria was not observed during the study time. No significant increase in total colony count was observed over the course of study in the frozen milk samples, whereas a significantly increased colony count was apparent by six hours for the fresh milk samples. Fat content of the milk decreased significantly within six hours for the frozen samples and within eight hours for the fresh milk. These data would suggest that when continuous drip feeding methods are employed for providing human milk to newborn infants, it may be desirable to change the entire feeding apparatus (syringe, tubing, and milk) at four hour intervals in order to optimize caloric intake and minimize the risk of bacterial overgrowth.

The composition of specialized formulas for infants who experience malabsorption or formula intolerance is described in detail. The limited studies of efficacy, as well as a rationale for selecting an appropriate formula for infants with malabsorption or formula intolerance, are discussed. Infants with symptoms of diarrhea or emesis may have intolerance to milk lactose or milk protein. Soy formulas contain no lactose or cow's milk and should be the first choice of an alternative feeding because of cost and convenience. Some infants may be intolerant of soy as well as cow's milk protein. They benefit from formula containing neither cow's milk nor soy protein or from a specially processed milk-based formula containing hydrolyzed casein. A carbohydrate-free formula to which the desired type of carbohydrate is added may be helpful in the diagnosis and treatment of disaccharidase deficiencies and monosaccharide intolerances. Infants with extensive intestinal resections or intractable diarrhea may require specialized infant formulas with qualitative/quantitative modifications of fat, carbohydrate, and protein. Formulas with medium-chain triglycerides may be useful for infants with steatorrhea. "Preterm" formulas or milk from the infant's mother are preferred for preterm infants, since such feedings promote improved fat and carbohydrate absorption and better meet the infant's nutrient requirements.

Growth and feeding outcomes during the first weeks of life were prospectively evaluated in 207 critically ill, very low-birth-weight (VLBW) infants (birth weight less than 1,500 gm). Maximal weight loss occurrd by day 9, averaging 13 percent of birth weight, while birth weight was regained by day 18. Energy intake during initial weight gain (19 gm. per day) averaged 100 kcal per kilogram. Feeding and growth outcome were highly correlated (p of less than 0.001) with severity of illness but were not significantly related to sex, birth weight, or appropriateness of weight for gestational age.