Nitrogen and mineral balance in preterm infants fed human milks or formula

Growth as well as nitrogen, calcium, sodium, and potassium balances were evaluated in 16 preterm infants weighing less than 1,600 g at birth, who were fed either their mother's milk, donated mature human milk, or standard commercial formula. Birthweight, gestational age, age of balance, and energy and fluid intakes were similar between groups. There were no differences between groups in the rate of growth. The infants fed their mother's milk (obtained 11-30 days into lactation) demonstrated nutrient balance similar to infants fed mature human milk. Infants fed standard commercial formula demonstrated significantly greater intake and retention of calcium compared to either human milk group. Infants fed either their mother's milk or mature human milk demonstrated net nitrogen and calcium retention below estimates of fetal nitrogen and calcium accretion. Infants fed standard formula demonstrated retentions that more closely approach the fetal estimates. This study did not demonstrate an advantage to feeding premature infants their mother's milk when compared to the feeding of mature donor milk.     

A pilot study of milk odor effect on nonnutritive sucking by premature newborns

OBJECTIVE: To study the effect of milk odor on nonnutritive sucking by premature newborns. DESIGN: Blinded, crossover study of the effects of milk vs sham odor on nonnutritive sucking. SETTING: Urban neonatal intensive care unit. PATIENTS: Twenty-nine premature newborns with gestational age of 29 to 36 weeks. INTERVENTION: Fourteen subjects were tested with fortified breast milk odor (group 1) and 15 were tested with formula odor (group 2). For the test observation, milk odor was directed to the nose (orthonasal exposure) using a specially modified pacifier. For the control observation, water was used as a sham odor. Observations were made concurrently with tube feeding of the newborn with either fortified breast milk (group 1) or formula (group 2). MAIN OUTCOME MEASURES: Total number of sucks and sucking bursts, measured from a digital record of pressure changes within the pacifier. RESULTS: Nutrient odor increased suck bursts in group 1 subjects, with borderline statistical significance (46.6 bursts/10 min with odor [95% confidence interval (CI), 39-54] vs 35.4 bursts/10 min without odor [95% CI, 28-43]). Unexpectedly, when test and control observations were combined, subjects in group 1 showed an overall increase in number of sucks (260.4 [95% CI, 206-315]) and suck bursts (41.0 [95% CI, 36-46]) compared with group 2 subjects (144.8 [95% CI, 87-203] vs 27.4 [95% CI, 21-34]). CONCLUSIONS: Nutrient odor exposure via pacifier may stimulate nonnutritive sucking during gavage feeding of premature newborns. Further studies on the effects of nutrient odor on nonnutritive sucking by premature newborns must take into account the effects of nutrients given via gavage.     

The effect of the odour of mother's milk on breastfeeding behaviour of premature neonates

AIM: To assess the effects of exposure to the odour of mother's milk on breastfeeding behaviour of premature neonates. METHODS: Thirteen preterm infants born at 30-33 weeks gestational age were tested. Seven infants were randomly assigned to the milk-odour condition, 6 to the water-control condition. During week 35 post-conceptual age, each baby was exposed to the appropriate odour stimulus for 120 sec. on 5 consecutive days immediately prior to a breastfeeding attempt. The breastfeeding bout following the final odour exposure session, and a second breastfeeding session shortly before the baby left the hospital, were analysed. Babies were weighed before and after each feeding session. RESULTS: During each breastfeeding session, babies in the milk-odour condition displayed longer sucking bouts and more bursts composed of >7 sucking movements, and also consumed more milk than the Control infants. The time spent in the hospital was significantly less for the milk-odour condition (median = 43 days vs. 55.5 days for Controls). CONCLUSION: Brief exposure to the odour of mother's milk prior to early breastfeeding trials had a positive effect on sucking behaviour and milk ingestion of preterm babies, which in turn resulted in a shortened stay in the hospital.     

Early follow-up of very low birth weight infants after hospital discharge with respect to growth and mineral homeostasis

Very low birth weight infants from two previous in-hospital feeding studies were investigated at follow-up after hospital discharge at a mean postnatal age of 12 weeks. Of infants who had received human milk in hospital (own mother's or pooled), 26 were seen at follow-up, of whom only 8 remained exclusively breast fed. Of those fed a formula in hospital, 31 were seen at follow-up. Those infants who had been fed human milk while in hospital demonstrated slower linear growth over the 6-week period of this study. Only those fed exclusively human milk from birth to the time of follow-up showed elevated serum alkaline phosphatase and low serum phosphate values, while those fed human milk in hospital, but completely or partially formula fed thereafter, had values similar to those fed formula throughout. Alkaline phosphatase values greater than 675 IU/L were associated with either exclusive breast feeding or vitamin D depletion. Of the two cases of rickets diagnosed on wrist x-rays, one infant had been exclusively breast fed and the other was vitamin D depleted.     

Premature infants fed mothers' milk to 6 months corrected age demonstrate adequate growth and zinc status in the first year

The objective of this investigation was to describe zinc status to 12 months corrected age in premature infants fed their mother's milk in relation to nutritional management in hospital and post-hospital discharge. Twenty-five premature infants fed their mother's milk in hospital were randomized to receive either a multi-nutrient fortifier (MNF), providing protein, calcium, phosphorus and zinc (MM + MNF) or calcium and phosphorus alone (MM + CaGP). Twelve preterm infants fed a preterm formula (PTF) served as a comparison group. At 35 weeks post-menstrual age zinc retention was determined using the stable isotope tracer 70Zn. After hospital discharge infants in MM + MNF and MM + CaGP were designated to a mother's milk-feeding group to 6 months corrected age (Post-MM) or formula feeding group (Post-FF) based on parental choice of feeding practice. Anthropometry was performed at term, three, 6 and 12 months corrected age. At 6 and 12 months corrected age a hair sample was obtained to determine hair zinc concentrations. Preterm infants receiving supplemental zinc in hospital, as MNF, had significantly greater zinc retention in hospital compared to MM + CaGP but not greater hair zinc concentrations at 6 or 12 months corrected age. Despite significantly lower zinc intakes to 6 months corrected age, Post-MM had significantly greater hair zinc concentrations at 6 months compared to PTF (median[25-75th percentile]: 146[106-190] versus 85[54-91] microg/g, P < 0.05). Hair zinc in Post-FF (124[77-163] microg/g) was lower than Post-MM, but this was not significant (P = 0.09). Only in Post-MM were hair zinc concentrations above the median of reference values from term born infants at 12 months corrected age. Mean values of weight, length and head circumference of the preterm infants in Post-MM, Post-FF and PTF groups were between the 3rd and 97th percentiles derived from WHO reference growth standards for mother's milk-fed term infants. Our findings suggest that supplemental zinc either in hospital or post-hospital discharge does not appear to be required for preterm infants fed their mother's milk.     

IMMUNOLOGIC CONSEQUENCES OF FEEDING INFANTS WITH COW MILK AND SOY PRODUCTS

ABSTRACT. Various products and regimens proposed for feeding infants when the mother's milk is not available have been evaluated intensively for capacity to achieve optimal nutrition. The immunologic consequences of feeding the foreign proteins contained in the various products have received much less attention and no systematic investigations have been done for comparable immunologic evaluation. Sera obtained at intervals from normal infants fed cow milk and soybean products from birth in different regimens were analyzed for antibodies to five major milk proteins and a soy protein isolate. Antibody levels increased slowly during the first 4 months, reaching a peak about 6 months of age. In infants fed cow milk products or a soy product from birth to 112 days of age and then given various cow milk products the following antibody responses were observed: The level of serum antibodies attained was highest with pasteurized cow milk and lower with heat-treated cow milk or a milk base formula of lower protein content. Feeding a soy product from birth for 112 days did not prevent a brisk antibody response to cow milk introduced subsequently, comparable to or greater than the antibody response seen when cow milk products were fed from birth. Clinically no immunologic disorders were detected in association with antibody responses to the various products and regimens. The implications of the findings for infant feeding and immunologic disorders are discussed.     

Immunologic consequences of feeding infants with cow milk and soy products

Various products and regimens proposed for feeding infants when the mother's milk is not available have been evaluated intensively for capacity to achieve optimal nutrition. The immunologic consequences of feeding the foreign proteins contained in the various products have received much less attention and no systematic investigations have been done for comparable immunologic evaluation. Sera obtained at intervals from normal infants fed cow milk and soybean products from birth in different regimens were analyzed for antibodies to five major milk proteins and a soy protein isolate. Antibody levels increased slowly during the first 4 months, reaching a peak about 6 months of age. In infants fed cow milk products or a soy product from birth to 112 days of age and then given various cow milk products the following antibody responses were observed: The level of serum antibodies attained was highest with pasteurized cow milk and lower with heat-treated cow milk or a milk base formula of lower protein content. Feeding a soy product from birth for 112 days did not prevent a brisk antibody response to cow milk introduced subsequently, comparable to or greater than the antibody response seen when cow milk products were fed from birth. Clinically no immunologic disorders were detected in association with antibody responses to the various products and regimens. The implications of the findings for infant feeding and immunologic disorders are discussed.     

Energy expenditure in human milk- versus formula-fed preterm infants

OBJECTIVE: We compared energy expenditure (EE) of preterm infants fed their mother's milk versus preterm infant formula.Study design A prospective, randomized crossover study of 13 healthy, appropriate weight for gestational age, gavage-fed, preterm infants. Before the study and according to our feeding protocol, infants uniformly received alternate feeds of human milk and formula. Each infant was randomly assigned to 24 hours of formula feeding followed by 24 hours of breast milk or the reverse. Infants were studied asleep, at the end of each 24-hour period. EE was measured by indirect calorimetry 1 hour before feeding, 20 minutes during feeding, and 1 hour after feeding in a servo-controlled convective incubator. Energy content of human milk was analyzed by bomb calorimetry. RESULTS: EE was significantly lower in breast milk-fed infants during prefeeding (52+/-6 vs 57+/-10 kcal/kg per 24 hours) (P<.05), per feeding (55+/-6 vs 60+/-10 kcal/kg per 24 hours) (P<.05), and at the postfeeding measurement (60+/-7 vs 65+/-7 kcal/kg per 24 hours) (P=.059). After correction of the results for the actual measured energy intake, all statistical differences reached the <.05 level. CONCLUSIONS: Preterm infants have lower EE when they are fed breast milk than when they are fed preterm infant formula.     

The effect of food supplements on the bioavailability of breast milk for premature infants--fecal fat and carbohydrate excretion

Faecal excretion of fat and carbohydrates was studied in 14 preterm infants fed on raw mother's milk (group I) or banked fortified human milk (group II) at days 7, 14, 21 and 28 of postnatal life: group I: n = 5; 31.0 +/- 2.0 weeks; 1954 +/- 441 g; group II: n = 9; 32.0 +/- 1.0 weeks; 1806 +/- 176 g. Mixtures of amino acids, peptides, minerals, dextrine and maltose were designed for fortifying banked human milk. There were no significant differences between faecal excretion of fat and carbohydrates in both feeding groups. The investigated human milk fortifier helps to realize the protein-energy ratio needed in preterm infants with well tolerable volumes of feeding and without stressing their limited digestive capacity.     

Diet and bone mineral content at term in premature infants

Premature infants are at risk of developing metabolic bone disease mainly because of low calcium and phosphorus intake. We have examined the effect of different mineral supplements on bone mineral content at term in 127 premature infants with gestational age <32 wk in a double-blinded randomized trial. We used either phosphate supplementation of human milk as recommended by the European Society of Pediatric Gastroenterology and Nutrition or fortified supplementation with protein, calcium, and phosphorus or preterm formula as recommended by the American Academy of Pediatrics. The intervention period was from 1 week old until 36 wk of gestational age, and the infants were fed approximately 200 mL x kg(-1) x d(-1). Bone mineral content was measured at term by dual-energy x-ray absorptiometry scan. Surprisingly, neither phosphate, fortifier, nor preterm formula supplementation had any significant effect on bone mineral content at term compared with infants fed their own mother's milk only. There was a tendency to higher total bone mineral content in infants fed preterm formula compared with infants fed their own mother's milk only (p = 0.05), but when the bone mineral content was corrected for the size of the infant, there was no difference (p = 0.68). Infants fed preterm formula had a significantly higher weight at term compared with infants fed their own mother's milk only (p = 0.02), but did not differ significantly in length or head circumference. In a regression analysis, the amount of supplemented phosphorus was significantly associated with weight at term (p = 0.008). We conclude that when feeding 200 mL x kg(-1) x d(-1), mineral supplementation of human milk or use of preterm formula does not significantly improve bone mineralization outcome at term.     

Clinical experience with preterm formulas in very low birthweight infants

Infants below 1500 g at birth were randomly assigned to receive one of two preterm infant formulars: S26 Low Birthweight (S26-LBW, 25 infants) or Enfalac Premature (EPF, 24 infants). They were either exclusively formula-fed (13 infants) or the formula was used to supplement their own mother's fresh breast milk (36 infants). The mean age when milk feeds were commenced was 7 days and the mean age when birthweight was regained was 12 days. The mean age when 2000 g was reached was 45 days at which time 10 (20%) infants were below the tenth centile on the intrauterine growth chart. None of the above variables were significantly different between the S26-LBW and EPF groups. However, the S26-LBW group established full enteral feeding significantly earlier compared to the EPF group (42 versus 64 d) and the number with adverse gastrointestinal effects was lower (4 versus 10 infants). Both preterm infant formulas supported a growth rate in excess of that in utero without stressing the infants' metabolic system. The growth rate of infants fed preterm breast milk supplemented with preterm infant formula was quantitatively similar to those exclusively fed preterm infant formula.     

Decreased ventilation in preterm infants during oral feeding

As respiratory difficulty may accompany nipple feeding in preterm neonates, we studied the effect of oral feeding on ventilation in 23 preterm infants. The infants composed two groups based on their postconceptional age at the time of study: Group A comprised 12 infants 34 to 35.9 weeks of age, and group B, 11 infants 36 to 38 weeks. Ventilation was measured via a nasal mask pneumotachometer, and sucking pressure via a nipple that also permitted milk delivery; transcutaneous PO2 and PCO2 were continuously monitored. The feeding pattern comprised an initial period of continuous sucking of at least 30 seconds, followed by intermittent sucking bursts for the remainder of the feed. When compared with an initial semi-upright control period, minute ventilation (V1) during continuous sucking fell by 52 +/- 6% (P less than 0.001) and 40 +/- 2% (P less than 0.001) in groups A and B, respectively. This was the result of a decrease in respiratory frequency and tidal volume and was associated with a fall in TcPO2 of 13 +/- 4 mm Hg (P less than 0.01) in group A and 10 +/- 2 mm Hg (P less than 0.01) in group B. During intermittent sucking, V1 and TcPO2 recovered partially only in the more mature infants (group B). At the end of the feed, TcPCO2 have risen by 3 +/- 1 mm Hg (P less than 0.001) in group A and by 2 +/- 2 mm Hg (P less than 0.05) in group B. Thus oral feeding results in an impairment of ventilation during continuous sucking and the subsequent recovery during intermittent sucking is dependent on postconceptional age.     

Clinical effects of oral motor intervention combined with non-nutritive sucking on oral feeding in preterm infants with dysphagia

ObjectiveTo explore the effectiveness of oral motor intervention combined with non-nutritive sucking in treating premature infants with dysphagia.MethodsSixty preterm infants admitted to the neonatal intensive care unit of the present study's hospital were selected and randomly divided into the control and intervention groups. The control group was given non-nutritive sucking intervention alone, while the intervention group was given oral motor intervention combined with non-nutritive sucking. The oral motor ability, milk sucking amount and sucking rate, feeding efficiency and outcomes, and the occurrence of adverse reactions were measured and compared.ResultsCompared to first-day interventions, preterm infant oral feeding readiness assessment scale-Chinese version (PIOFRAS-CV) scores of the two groups significantly increased after 14 days of intervention, and this score was higher in the intervention group compared to the control group. Similarly, after 14 days of intervention, the intervention group's milk sucking rate and amount were significantly higher than the control group. Also, after the intervention, the intervention group's total oral feeding weeks were considerably lower, while the feeding efficiency and body weight were significantly higher than the control group. Moreover, the overall adverse reaction rate in the intervention group was lower than that in the control group.ConclusionsOral motor intervention combined with non-nutritive sucking can significantly improve the oral motor ability of premature newborns, promote the process of oral feeding, improve the outcome of oral feeding, and reduce the occurrence of adverse effects. The combined intervention seems to have a beneficial effect on oral feeding proficiency in preterm infants.     

Changes in the fatty acids pattern of red blood cell phospholipids induced by type of milk, dietary nucleotide supplementation, and postnatal age in preterm infants

The fatty acid profile of red blood cell phospholipids and the total phospholipid and cholesterol contents of erythrocyte membrane in preterm infants in the first month of life were studied. Influences of human milk and adapted formula and dietary nucleotides supplementation at a level similar to that found in human milk were evaluated. Nineteen preterm newborn infants with adequate weight for gestational age were fed their own mother's preterm human milk, 18 with a standard milk formula and 18 with the same formula supplemented with nucleotides. Blood samples were obtained at birth from cord blood, and at 30 days of age. At 1 month of life, linoleic acid rose in formula fed infants compared to those fed human milk (p less than 0.05) and relative amounts of 20:3w6, 20:4w6, 22:4w6, 22:5w6, and total polyunsaturates of the w6 series greater than 18 carbon atoms were significantly decreased in standard milk formula fed infants (p less than 0.05-0.01). No significant differences for these fatty acids were found between human milk and nucleotide milk formula infants. Docosahexaenoic acid (22:6w3) decreased from birth to 1 month of age in formula fed infants (p less than 0.01) but not in human milk fed infants. Infants fed nucleotide milk formula showed intermediate values for 20:3w6 and 20:4w6 (p less than 0.1) between infants fed human milk and those fed standard milk formula.(ABSTRACT TRUNCATED AT 250 WORDS)     

Randomized, multicenter trial of two different formulas for very early enteral feeding advancement in extremely-low-birth-weight infants

BACKGROUND: In extremely-low-birth-weight (ELBW) infants, formula feeding is required if human milk is not available. The tolerance of a new 'high' lactose (55 g/L), low protein, low phosphate, hydrolyzed protein formula (HLF) for early enteral feeding advancement of ELBW infants was compared with that of a low lactose (1 g/L) hydrolyzed protein formula (LLF). METHODS: In a randomized multicenter trial, 99 ELBW infants were fed according to a standardized protocol beginning at 48 hours of age with 12 ml/kg daily increments. Primary outcome was the cumulative milk feeding volume (CFV) from days 3 to 14. The authors hypothesized that feeding HLF as a supplement to human milk would increase the CFV at least by 20% in at least 60% of matched pairs compared with LLF. A secondary issue was to investigate whether human milk would increase the CFV compared with formula. RESULTS: The CFV was 720 mL/kg (range, 0-962 mL/kg) with HLF and 613 mL/kg (range, 3-1,283 mL/kg) with LLF feeding. There was no 20% difference. On day 14, the median feeding volume was 103 mL/kg. The CFV was 533 mL/kg (range, 0-962 mL/kg) in infants who received less than 10% of human milk and 832 mL/kg (range, 74-1,283 mL/kg) in infants who received more than 10%. Necrotizing enterocolitis (Bell stage > or =2) occurred only with LLF feeding (n = 5; P < 0.05). CONCLUSIONS: The study failed to find the hypothesized 20% advantage of the new HLF. The observed advantage of human milk supports the hypothesis that it should be the first diet in ELBW infants; however, this hypothesis still must be confirmed in a controlled, randomized trial.     

母乳及配方奶对早产儿胃排空功能的影响

目的 探讨母乳及配方奶对早产儿消化道生长发育的影响。方法 将33例早产儿随机分成母乳及配方奶喂养组,采用B型实时超声显像法测定其生后d5、7、10胃排空变化,并检测开奶前、生后d5空腹时血胃动素、一氧化氮（NO）水平。结果 两组早产儿随日龄增长,50％胃排空时间逐渐缩短。母乳喂养儿d5、d750％胃排空时间短于奶方喂养儿,差异有显著意义（P均＜0.05）。生后d5奶方喂养儿胃动素水平低于母乳喂养儿（P＜0.05）,NO水平明显高于母乳喂养儿（P＜0.01）。结论 母乳喂养儿较奶方喂养儿胃排空功能成熟快。     

Supplementation of a bovine milk formula with an oligosaccharide mixture increases counts of faecal bifidobacteria in preterm infants

BACKGROUND: The establishment of a balanced intestinal microflora which may protect against infection is desirable for the preterm infant. OBJECTIVE: To investigate the effect of a preterm formula milk supplement consisting of oligosaccharides in similar proportions to human milk on the faecal flora and stool characteristics of preterm infants. STUDY DESIGN: To resemble the effect of human milk, an oligosaccharide mixture consisting of 90% galacto-oligosaccharides and 10% fructo-oligosaccharides was used to supplement a standard preterm formula at a concentration of 10 g/l. This supplemented formula was studied in 15 preterm infants, and the results were compared with those found in 15 infants fed a formula supplemented with maltodextrin as placebo. A group fed fortified mother's milk was investigated as a reference group (n = 12). On four days during a 28 day feeding period (1, 7, 14, and 28), the faecal flora was investigated, and stool characteristics, growth, and possible side effects were recorded. RESULTS: During the study period, the number of bifidobacteria in the group fed the oligosaccharide supplemented formula increased to the upper range of bifidobacteria counts in the reference group. The difference between the supplemented and non-supplemented groups was highly significant (p = 0.0008). The stool characteristics were also influenced by the supplement: the stool frequency after 28 days was significantly lower in the control group than in the oligosaccharide supplemented group (p = 0.0079) and the reference group (p < 0.0001). Over the study period, the stool consistency in the control group became harder, but remained fairly stable in the other two groups. There was no effect of the different diets on the incidence of side effects (crying, regurgitation, vomiting) or on weight gain or length gain. CONCLUSION: Supplementing preterm formula with a mixture of galacto- and fructo-oligosaccharides at a concentration of 10 g/l stimulates the growth of bifidobacteria in the intestine and results in stool characteristics similar to those found in preterm infants fed human milk. Therefore prebiotic mixtures such as the one studied may help to improve intestinal tolerance to enteral feeding in preterm infants.     

Cow milk feeding in infancy: further observations on blood loss from the gastrointestinal tract

Because feeding of cow milk causes normal infants to lose increased amounts of occult blood from the gastrointestinal tract, we conducted a prospective trial to measure intestinal blood loss quantitatively and to monitor iron nutritional status. Fifty-two infants entered the trial at 168 days of age and were assigned at random to receive either cow milk or a milk-based formula. Initially, 31 infants had been breast-fed and 21 had been fed formulas. With the feeding of cow milk, the proportion of guaiac-positive stools increased from 3.0% at baseline to 30.3% during the first 28 days of the trial (p less than 0.01), whereas the proportion of positive stools remained low (5.0%) with the feeding of formula. The proportion of guaiac-positive stools among cow milk-fed infants declined later, but for the entire trial it remained significantly (p less than 0.01) elevated. Stool hemoglobin concentration increased markedly with the introduction of cow milk, rising from a mean (+/- SD) of 622 +/- 527 micrograms/gm dry stool at baseline to 3598 +/- 10,479 micrograms/gm dry stool during the first 28 days of ingestion of cow milk. Among infants fed formula, stool hemoglobin did not increase and was significantly (p less than 0.01) less than in the cow milk group. Among infants fed cow milk, the increase in hemoglobin concentration tended to be greater for those who had initially been fed human milk than for those who had initially been fed formulas. Iron nutritional status was not significantly different between the two feeding groups. However, one infant became iron deficient after 4 weeks of ingesting cow milk. We conclude that cow milk feeding leads to increased intestinal tract blood loss in a large proportion of normal infants and that the amount of iron lost is nutritionally important.     

Three-year growth and developmental follow-up of very low birth weight infants fed own mother's milk, a premature infant formula, or one of two standard formulas

A cohort of 40 very low birth weight (VLBW) infants was followed until they reached 3 years of age. These infants were originally part of a feeding trial in the early postnatal period whereby they were fed either their own mother's milk, a standard whey-predominant formula, a casein-predominant formula, or a premature formula. Those fed the latter formula grew significantly better while in the hospital and had no biochemical derangements. At 3 years of age, there were no significant intergroup differences with respect to growth or development. There was a positive correlation between head growth in hospital and weight at 3 years, but there were no other significant relationships between early postnatal growth and growth parameters at 3 years. Socioeconomic status was the only predictor of developmental scores at 3 years of age. No adverse effects from early metabolic acidosis or alterations of amino acid profiles during the neonatal period were detectable at 3 years of age. However, the small sample size of this study may have missed true differences in outcome measures at 3 years, and larger studies are required to examine these questions further.