Enhanced growth of preterm infants fed a new powdered human milk fortifier: A randomized, controlled trial

Powdered to Liquid Human Milk Fortifiers in the Preterm Infant

In preterm infants, the goal of aggressive extrauterine nutritional management is to mimic in utero growth and nutrient accretion. Over the latter half of the 20th century, nutritional optimization through the practice of fortifying human milk rose to practice with increased survival rates in preterm infants of younger gestational age. The quest for optimal preterm fortification and nutrition remains a contentious area of debate. This review aims to summarize the historical perspectives of human milk fortification as well as the current literature advocating for the use of liquid human milk fortifiers in enterally fed premature infants.

Individualized target fortification of breast milk with protein, carbohydrates, and fat for preterm infants: A double-blind randomized controlled trial

BACKGROUND & AIMS

In preterm infants, natural variation of breast milk composition makes it difficult to achieve recommended macronutrient intakes with standard fortification. Evidence suggests that nutritional deficiency induces poor postnatal growth. This study investigates impacts of target fortification on preterm growth and metabolism by adjusting breast milk macronutrients.

METHODS

This study was conducted as a single-centre, double-blind, randomized controlled trial for infants <30 gestational weeks. The control group received standard fortification and the intervention group received standard plus target fortification adding modular protein, lipids, and carbohydrates. Breast milk content was measured 3x/week using a validated near-infrared bedside spectrometer (NIRS). Modulars were added to achieve recommended values. To assess total nutrient intake, all 2810 native breast milk samples were analyzed - protein and fat using bedside-NIRS, lactose using tandem mass spectrometry (UPLC-MS/MS). Body composition was measured using air displacement plethysmography. Primary outcome was weight gain during the first 21 days of intervention.

RESULTS

Baseline characteristics, morbidities, and total fluid intake were not different between groups (intervention n = 52, control n = 51). The intervention group infants had higher macronutrient intakes, weight gain (21.2 ± 2.5 vs 19.3 ± 2.4 g/kg/d, mean difference: 1.9 g/kg/d, 95% CI: 0.9 - 2.9), and body weight. Infants in the intervention group from mothers with below-average breast milk protein content showed greatest impact on weight at 36 weeks (2580 ± 280 g vs 2210 ± 300 g), length, head circumference, fat, and fat-free mass. Also, feeding intolerance was less frequent, blood urea was higher, and triglycerides were lower.

CONCLUSIONS

This study provides evidence that target fortification of breast milk with low macronutrient content enhances the quality of nutrition and growth and is feasible in clinical routine.

Nutrient enrichment of human milk with human and bovine milk-based fortifiers for infants born weighing <1250 g: a randomized clinical trial

Background

Human milk-based fortifiers (HMBFs) are being adopted in neonatal care to enrich the nutrients in human milk for very low birth weight (VLBW) infants despite being costly and there being limited efficacy data. No randomized clinical trial has evaluated the use of HMBF compared with bovine milk-based fortifiers (BMBFs) in the absence of formula feeding.

Objective

To determine if HMBF compared with BMBF for routine nutrient enrichment of human milk improves feeding tolerance, reduces morbidity, reduces fecal calprotectin (a measure of gut inflammation), and supports the growth of infants <1250 g.

Design

In this blinded randomized clinical trial, infants born weighing <1250 g were recruited from neonatal units in Ontario, Canada between August 2014 and November 2015. The infants were fed mother's milk and donor milk as required. Fortification commenced at 100 mL/kg per day of HMBF (0.81 kcal/mL) or BMBF (0.72 kcal/mL) and advanced at 140 mL/kg per day to 0.88 and 0.78 kcal/mL, respectively. The primary outcome was percentage of infants with a feeding interruption for ≥12 h or a >50% reduction in feeding volume. Secondary outcomes included a dichotomous mortality and morbidity index (i.e., affirmative for any one of death, late-onset sepsis, necrotizing enterocolitis, chronic lung disease, or severe retinopathy of prematurity), fecal calprotectin, and growth.

Results

Of 232 eligible infants, 127 (54.7%) were randomized (n = 64 HMBF, n = 63 BMBF). Mean ± SD birth weight and gestational age of infants were 888 ± 201 g and 27.7 ± 2.5 wk, respectively. No statistically significant differences were identified in feeding interruptions [17/64 HMBF, 20/61 BMBF; unadjusted risk difference: -6.2% (95% CI: -22.2%, 9.8%)]. There was no statistically significant difference in the mortality and morbidity index (48.4% HMBF, 49.2% BMBF, adjusted P = 0.76), changes in fecal calprotectin, or growth z scores.

Conclusions

Among infants born weighing <1250 g and exclusively fed human milk, the use of HMBF did not improve feeding tolerance or reduce mortality and morbidity compared with BMBF. This trial was registered at clinicaltrials.gov as NCT02137473.

Growth and Nutritional Biomarkers of Preterm Infants Fed a New Powdered Human Milk Fortifier: A Randomized Trial

OBJECTIVES

The aim of this study was to assess growth and nutritional biomarkers of preterm infants fed human milk (HM) supplemented with a new powdered HM fortifier (nHMF) or a control HM fortifier (cHMF). The nHMF provides similar energy content, 16% more protein (partially hydrolyzed whey), and higher micronutrient levels than the cHMF, along with medium-chain triglycerides and docosahexaenoic acid.

METHODS

In this controlled, multicenter, double-blind study, a sample of preterm infants ≤32 weeks or ≤1500 g were randomized to receive nHMF (n = 77) or cHMF (n = 76) for a minimum of 21 days. Weight gain was evaluated for noninferiority (margin = -1 g/day) and superiority (margin = 0 g/day). Nutritional status and gut inflammation were assessed by blood, urine, and fecal biochemistries. Adverse events were monitored.

RESULTS

Adjusted mean weight gain (analysis of covariance) was 2.3 g/day greater in nHMF versus cHMF; the lower limit of the 95% CI (0.4 g/day) exceeded both noninferiority (P < 0.001) and superiority margins (P = 0.01). Weight gain rate (unadjusted) was 18.3 (nHMF) and 16.8 g · kg · day (cHMF) between study days 1 and 21 (D1-D21). Length and head circumference (HC) gains between D1 and D21 were not different. Adjusted weight-for-age z score at D21 and HC-for-age z score at week 40 corrected age were greater in nHMF versus cHMF (P = 0.013, P = 0.003 respectively). nHMF had higher serum blood urea nitrogen, pre-albumin, alkaline phosphatase, and calcium (all within normal ranges; all P ≤ 0.019) at D21 versus cHMF. Both HMFs were well tolerated with similar incidence of gastrointestinal adverse events.

CONCLUSIONS

nHMF providing more protein and fat compared to a control fortifier is safe, well-tolerated, and improves the weight gain of preterm infants.

Fortification of human milk for preterm infants

Human milk is the preferred feeding for all infants, including those of very low birth weight (<1500 g). It has both nutritional and anti-infective properties which are especially important for infants at risk for sepsis and necrotizing enterocolitis. When maternal milk is not available or the amount produced is not sufficient to meet daily needs, donor human milk may (should) be used in its place. However, donor human milk is generally term in quality and likely has insufficient protein to promote appropriate growth. Whether donor or mother's own milk, fortification of human milk is required to meet nutrient requirements for growth and development for these preterm infants who are at high risk for growth faltering during the hospital stay. There are multiple strategies and products that may be employed to support desired growth rates. The advent of human milk analyzers may be helpful in a more customized approach to fortification.

Growth and Tolerance of Preterm Infants Fed a New Extensively Hydrolyzed Liquid Human Milk Fortifier

OBJECTIVES

This study was a comparison of growth and tolerance in premature infants fed either standard powdered human milk fortifier (HMF) or a newly formulated concentrated liquid that contained extensively hydrolyzed protein.

METHODS

This was an unblinded randomized controlled multicenter noninferiority study on preterm infants receiving human milk (HM) supplemented with 2 randomly assigned HMFs, either concentrated liquid HMF containing extensively hydrolyzed protein (LE-HMF) or a powdered intact protein HMF (PI-HMF) as the control. The study population consisted of preterm infants ≤33 weeks who were enterally fed HM. Infants were studied from the first day of HM fortification until day 29 or hospital discharge, whichever came first.

RESULTS

A total of 147 preterm infants were enrolled. Noninferiority was observed in weight gain reported in the intent-to-treat (ITT) analysis was 18.2 and 17.5 g · kg(-1) · day(-1) for the LE-HMF and PI-HMF groups, respectively. In an a priori defined subgroup of strict protocol followers (n = 75), the infants fed LE-HMF achieved greater weight over time than those fed PI-HMF (P = 0.036). The LE-HMF group achieved greater linear growth over time compared to the PI-HMF (P = 0.029). The protein intake from fortified HM was significantly higher in the LE-HMF group compared with the PI-HMF group (3.9 vs 3.3 g · kg(-1) · day(-1), P < 0.0001). Both fortifiers were well tolerated with no significant differences in overall morbidity.

CONCLUSIONS

Both fortifiers showed excellent weight gain (grams per kilograms per day), tolerance, and low incidence of morbidity outcomes with the infants who were strict protocol followers fed LE-HMF having improved growth during the study. These data point to the safety and suitability of this new concentrated liquid HMF (LE-HMF) in preterm infants. Growth with this fortifier closely matches the recent recommendations for a weight gain of >18 g · kg(-1) · day(-1).

How to find and how to read articles in neonatology

Staying abreast of the neonatal literature is an important task. Being aware of new information and knowing how to evaluate its reliability remain essential to be able to provide the most appropriate, evidence-based, therapy to our patients. This article discusses methods for being informed of, and critically reviewing, published research in order to fulfill these tasks without being overwhelmed by the number or complexity of publications.

Nutritional support for premature infants in the neonatal intensive care unit

Nutritional support for premature infants in the neonatal intensive care unit setting is complex. Such infants have conditions unique to this period of the lifespan requiring specialized care management, both of which may impede the provision of adequate nutrition to support basal metabolic needs. Premature infants require optimum nutritional intake to support rapid growth during a time when they are not fully capable of tolerating it. This article reviews developmental anatomy, physiology, and the effect of premature delivery by systems; the challenges of providing adequate nutrition; and current evidence-based strategies to provide nutrition for premature infants during hospitalization.

Target fortification of breast milk: how often should milk analysis be done?

Target fortification (TFO) reduces natural macronutrient variation in breast milk (BM). Daily BM analysis for TFO increases neonatal intensive care unit work load by 10-15 min/patient/day and may not be feasible in all nurseries. The variation of macronutrient intake when BM analysis is done for various schedules was studied. In an observational study, we analyzed 21 subsequent samples of native 24-h BM batches, which had been prepared for 10 healthy infants (gestational age 26.1 ± 1.3 weeks, birth weight: 890 ± 210 g). Levels of protein and fat (validated near-infrared milk analyzer), as well as lactose (UPLC-MS/MS) generated the database for modelling TFO to meet recommendations of European Society for Paediatric Gastroenterology Hepatology and Nutrition. Intake of macronutrients and energy were calculated for different schedules of BM measurements for TFO (n = 1/week; n = 2/week; n = 3/week; n = 5/week; n = 7/week) and compared to native and fixed dose fortified BM. Day-to-day variation of macronutrients (protein 20%, carbohydrate 13%, fat 17%, energy 10%) decreased as the frequency of milk analysis increased and was almost zero for protein and carbohydrate with daily measurements. Measurements two/week led to mean macronutrient intake within a range of ± 5% of targeted levels. A reduced schedule for macronutrient measurement may increase the practical use of TFO. To what extent the day-to-day variation affects growth while mean intake is stable needs to be studied.

Protein Intake and Growth in Preterm Infants: A Systematic Review

Objective. This review aimed to investigate the relationship between varying levels of enteral protein intake and growth in preterm infants, regardless of feeding method. Data Sources. Electronic databases were searched for relevant studies, as were review articles, reference lists, and text books. Study Selection. Trials were included if they were randomized or quasirandomized, participants were <37 weeks gestation at birth, and protein intakes were intentionally or statistically different between study groups. Trials reporting weight, length, and head circumference gains in infants fed formula, human milk, or fortified human milk were included. Data Extraction. Studies were categorized by feeding-type and relevant data were extracted into summary tables by one reviewer and cross-checked by a second. Data Synthesis. A meta-analysis could not be conducted due to extensive variability among studies; thus, results were synthesized graphically and narratively. Twenty-four trials met the inclusion criteria and were included in a narrative synthesis and 19 in a graphical synthesis of study results. Conclusions. There was extensive variability in study design, participant characteristics, and study quality. Nonetheless, results are fairly consistent that higher protein intake results in increased growth with graphical representation indicating a potentially linear relationship. Additionally, intakes as high as 4.5 g/kg/day were shown to be safe in infants weighing >1000 g.

Population-based study shows improved postnatal growth in preterm very-low-birthweight infants between 1995 and 2010

AIM

To assess whether the postnatal growth of preterm very-low-birthweight (VLBW) infants, as determined by measures of postnatal growth failure (PNGF), improved during the period 1995-2010 and to evaluate postnatal growth by gestational age (GA) and intrauterine growth groups.

METHODS

The study was based on the Israel national VLBW infant database and comprised 13 531 VLBW infants of 24-32 weeks' GA, discharged at a postmenstrual age of ≤40 weeks. Z-scores were determined for weight at birth and discharge. Severe and mild PNGF was defined as a decrease >2 and 1-2 z-scores, respectively. Three time periods were considered: 1995-2000, 2001-2005 and 2006-2010. Multinomial logistic regression was used to assess the independent effect of time period on PNGF.

RESULTS

Severe PNGF decreased from 11.7% in 1995-2000 to 7.2% in 2001-2005 and 5.2% in 2006-2010. Infants born in 2006-2010 had sixfold lower odds for severe PNGF than babies born in 1995-2000 (adjusted odds ratio 0.17, 95% confidence interval 0.14-0.21) and <twofold lower odds for mild PNGF (adjusted odds ratio 0.42, 95% confidence interval 0.39-0.48).

CONCLUSION

We demonstrated a marked decline in PNGF among preterm VLBW infants from 1995-2000 to 2006-2010. This decline was even present in extremely premature infants.

Human milk fortifier: an occult cause of bowel obstruction in extremely premature neonates

BACKGROUND

Human milk fortifier (HMF) is used in neonatal units throughout North America to facilitate growth of preterm infants. Little data is available on the gastrointestinal side effects and potential adverse events. The purpose of this paper was to present a series of infants presenting with bowel obstruction associated with HMF.

METHODS

Cases of HMF obstruction were collected between January 2010 and December 2012. Charts were reviewed and relevant data was collected.

RESULTS

During the study period, 7 premature infants presented with bowel obstruction secondary to intestinal concretions of HMF. All babies were premature with gestational ages from 25 to 27 weeks. Birth weight was less than 1000 grams in all patients. Patients presented with feeding intolerance, bilious aspirates, abdominal distension, and obstipation. Four of the patients presented with acute deterioration and required urgent surgical intervention.

CONCLUSIONS

HMF is an important source of nutritional support in infants, which is felt to be safe. We present a series of infants where its use has resulted in significant complications. HMF should be used with caution in infants, especially those with a history of necrotizing enterocolitis. Further research should examine the calcium, protein, and fatty acid concentration tolerable in the gastrointestinal tract of infants.

Human milk fortification with differing amounts of fortifier and its association with growth and metabolic responses in preterm infants

BACKGROUND

Fortification of human milk (HM) is a common clinical practice to adapt breast milk to the nutritional needs of very low birth weight (VLBW) infants. The optimal method for HM fortification remains to be determined, and a variety of protocols are currently used in neonatal intensive care units.

OBJECTIVE

It is believed that standard fortification is insufficient to meet the needs of VLBW infants. Therefore, we designed a randomized prospective study that investigated the effects of varying levels of blind fortification on short-term growth and metabolic responses of preterm infants.

METHODS

Eligible infants were randomized into 3 groups: standard fortification (SF), moderate fortification (MF), and aggressive fortification (AF). Short-term growth, feeding intolerance, and urea, calcium, phosphorus, and alkaline phosphatase levels were assessed.

RESULTS

There were 26, 29, and 29 infants in the SF, MF, and AF groups, respectively. The baseline characteristics of the groups were similar. Daily weight gain and length at discharge did not differ among the groups; however, head circumference was significantly higher in the MF and AF groups compared with the SF group. Urea, calcium, phosphorus, and alkaline phosphatase levels were similar between the groups.

CONCLUSION

We demonstrated that blind fortification of HM, even with higher amounts than recommended by manufacturers, did not cause any measured adverse effects on the metabolic response of preterm infants. Anthropometric measurements (except head circumference) were not different between the different dosages of fortification.

Does milk fortification increase the risk of necrotising enterocolitis in preterm infants with congenital heart disease?

Prematurity and low birth weight adds to the risk of serious congenital heart disease in infants. It may also delay surgical intervention, especially when cardiopulmonary bypass is required, or where an aortopulmonary shunt is necessary to maintain adequate oxygenation. In this setting, neonatologists are faced with the challenge of accelerating the infant's growth to allow for early surgery. We describe the cases of two infants in whom an attempt to fortify the feeds was associated with necrotising enterocolitis, with a lethal outcome in one. The outcome suggests caution in fortifying feeds in premature infants with serious congenital heart disease.

Evaluation of human milk fortification from the time of the first feeding: effects on infants of less than 31 weeks gestational age

OBJECTIVE

To determine whether human milk fortification from the time of the first feeding significantly improves weight gain and bone mineral status in infants of <31 weeks estimated gestational age as compared with delayed or standard human milk fortification.

STUDY DESIGN

This was a retrospective pre-post design. In all, 95 infants born at <31 weeks estimated gestational age were compared. There were 53 infants in the early fortification group (EFG) and 42 infants in the delayed fortification group (DFG). They were compared with regard to weight gain at 34 weeks postmenstrual age (PMA), and their serum levels of calcium, phosphorus and alkaline phosphatase levels were compared as an indicator of bone mineral status. The practice change of fortifying all human milk given to preterm infants at <34 weeks PMA commenced in June 2009. The usual practice of fortification took place once an infant had reached a feeding volume of 50 to 100 ml kg(-1) per day. The new practice fortified all human milk with a powdered human milk fortifier to 24 calories per ounce, starting with the first feeding, no matter how small the volume.

RESULT

There were no differences in weight gain between the EFG and the DFG. The group that received fortification from the time of the first feeding were significantly less likely to have alkaline phosphatase levels >500 U l(-1) from 33 weeks PMA onward. There was no incidence of feeding intolerance with early fortification.

CONCLUSION

Fortification of human milk from the time of the first feeding does not affect weight gain at 34 weeks PMA, but is related to a lower incidence of elevated alkaline phosphate levels and does not cause feeding intolerance.

Randomized trial of enteral protein and energy supplementation in infants less than or equal to 1250 g at birth

OBJECTIVE

To determine if enteral protein and energy supplementation would significantly improve weight gain as compared with energy supplementation alone in <or=1250 g infants.

STUDY DESIGN

Inclusion criteria were birth weight (BW) <or=1250 g, postnatal age >or=14 days, diet of >or=75% enteral nutrition (fortified human milk or formula) and either failure to regain BW or weight gain<15 g kg(-1) per days. Infants were randomized to a multinutrient supplement that provided increased protein and energy (P/E) intake or energy alone (medium chain triglyceride oil, MCT). Growth rates were compared at the end of the 4-week study period.

RESULT

Of 30 eligible infants, 23 were enrolled, 12 received MCT (BW=862+/-252 g, mean+/-s.d.) and 11 received P/E (BW=879+/-241 g). Significantly higher protein intake (P/E=3.5+/-0.3 g kg(-1) per day, MCT=3.0+/-0.5 g kg(-1) per day) and better growth (P/E=17.0+/-2.4 g kg(-1) per day, MCT=11.5+/-4.8 g kg(-1) per day) were observed in the P/E group.

CONCLUSION

These data are consistent with the importance of providing additional daily protein intake to achieve increased postnatal growth in very low birth weight infants experiencing slow growth.

Fortification of maternal milk for very low birth weight (VLBW) pre-term neonates

Human milk is the best food for all neonates; however, in pre-term infants, especially those with a very low birth weight, it may lead to insufficient intake of protein and energy. The use of fortified human milk produces adequate growth in premature infants and satisfies the specific nutritional requirements of these babies. To improve the nutritional management of pre-term infants < or =35 weeks' gestational age, an individualised human milk fortification system based on the analysis of maternal milk was evaluated.

Human milk fortifiers in very low birth weight infants

The use of HMF remains an important option and has become common practice in all neonatal intensive care units. However, optimal composition of fortifiers is still undefined and more data are needed on safety and long-term benefits. Further research should be directed toward comparisons between different proprietary preparations, evaluating both short-term and long-term outcomes and adverse effects, in search of the best method of fortification.

Growth in high risk infants <1500 g birthweight during the first 5 weeks

BACKGROUND

Growth of very low birthweight (VLBW) infants is used to monitor nutrition and intrauterine velocity is taken as the desired goal.

AIM

We hypothesised that beside nutrition growth failure is caused by disease severity.

METHODS

Prospective longitudinal study of 45 VLBW infants undergoing intensive care, mechanical ventilation was used as proxy to disease severity. Nutritional intake, body weight, length, head circumference, and lower leg length (LLL) were measured during the first 5 weeks of life.

RESULTS

Birthweight and gestational age were lower in 22 ventilated than in 23 unventilated infants (p<0.01). Median daily intake was 3.2 and 2.8 g/kg for protein (n.s.), 108 and 112 kcal/kg for energy (n.s.), 175 and 160 ml/kg for volume (p<0.01) up to day 35, respectively. Chronic lung disease occurred in 12 infants, five of whom were treated with dexamethasone. Artificial ventilation (p<0.01) and dexamethasone treatment (p<0.05) were independent predictors of weight gain. Median weight gain (8.2 and 9.7 g/kg/d), head growth (0.45 and 0.60 cm/week), and LLL growth (0.28 and 0.35 mm/d) were lower (p<0.05) in ventilated than in non-ventilated infants, respectively. The correlation of LLL growth with body length (r=0.31, p<0.05) and head growth (r=0.42, p<0.01) was weak. Dexamethasone arrested growth; median LLL gain was 0.21 and 0.31 mm/d in ventilated infants with and without dexamethasone (p<0.05).

CONCLUSION

In VLBW infants, fetal growth rates are not reached with current feeding practice. In addition to inadequate nutrition, factors directly related to disease and treatment contribute to postnatal growth failure.

Enteral intake for very low birth weight infants: what should the composition be?

Providing optimal nutrition to satisfy the growth needs of very low birth weight infants is critical. The available preterm formulas and fortified human milk diets provide protein intakes of approximately 3.5 to 3.6 g/kg/d when volumes sufficient to provide 120 kcal/kg/d are fed to these infants. These intakes support growth and protein accretion at about or slightly greater than intrauterine rate and lead to relatively increased fat deposition. However, most very low birth infants fed these diets remain below the 10th percentile of the intrauterine growth standards at discharge. There is clear evidence that, with respect to growth, very low birth infants are likely to benefit from a higher protein intake; however, there is no clear evidence that energy intakes greater than 120 kcal/kg/d are needed. Although the upper limit of protein intake and the ideal protein:energy ratio remain controversial, there is enough evidence to support the beneficial and safe use of formulas providing protein:energy ratio of 3.2 to 3.3 g/100 kcal.

Enteral nutrition for premature infants: the role of human milk

Nutrition support of the premature infant must be designed to compensate for metabolic and gastrointestinal immaturity, immunologic insufficiency, and the demands of associated medical conditions. The beneficial effects of human milk extend to the feeding of premature infants. Although human milk enhances immunity, nutritional concerns arise because the milk might not meet the expanded nutrient requirements of very low birth weight premature infants. Human milk fortifiers are available to provide optimum nutrition. This chapter summarizes the benefits and limitations of human milk for the premature infant.

Benefits of maternal and donor human milk for premature infants

Nutrition support of the premature infant must be designed to compensate for metabolic and gastrointestinal immaturity, immunologic insufficiency, and the demands of associated medical conditions. The beneficial effects of human milk extend to the feeding of premature infants. While human milk enhances immunity, nutritional concerns arise because the milk may not meet the expanded nutrient requirements of the very low birth weight (VLBW, less than 1500 g) premature infant. Human milk fortifiers are available to provide optimum nutrition. This review summarizes the benefits and limitations of human milk for the premature infant.

Calcium nutrition and metabolism during infancy

Calcium is a vital mineral for the developing newborn infant. This review discusses perinatal and neonatal calcium metabolism, with an emphasis on enteral calcium absorption and the nutritional factors affecting calcium bioavailability including the three major endocrine hormones involved in calcium metabolism: parathyroid hormone, vitamin D, and calcitonin. The placenta transports calcium to the fetus throughout pregnancy, with the largest amount of fetal calcium accumulation occurring in the third trimester. At birth, the newborn transitions to intestinal absorption to meet the body's calcium needs. Most calcium is absorbed by paracellular passive diffusion in the small intestine. Calcium intestinal absorption is affected by the type and amount of calcium ingested. It is also affected by the amount of intestinal calcium that is bound to dietary fats and proteins. One major consequence of decreased calcium absorption is metabolic bone disease in which there is a failure of complete mineralization of the bone osteoid.

Pattern of daily weights among low birth weight neonates in the neonatal intensive care unit: data from a multihospital health-care system

OBJECTIVES

We sought to generate a contemporary postnatal weight grid for low birth weight (LBW, <2500 g) neonates using actual data, not mathematically derived idealized weight curves. To do this, we collected electronic data from all neonatal intensive care units (NICU) patients weighing 400-2600 g at birth, during 30 consecutive months (January 2003-June 2005) in all four NICU's within a single health system, Intermountain Health Care (IHC).

METHODS

A deidentified limited data set was collected from electronic IHC records. Data were limited to the birth weights and all subsequent daily weights, until discharge, death, or transfer to a non-IHC facility. Lines were drawn connecting the exact daily means of body weight for patients in 200 g birth weight groupings, ranging from 400 to 2600 g. We assessed differences in growth patterns predicted by this grid vs three previously published NICU longitudinal weight grids.

RESULTS

All recorded weights were electronically extracted for 1813 consecutive patients with dates of birth from January 1, 2003 through June 30, 2005. The daily weights of each patient totaled over 48,000 individual data points. The new grid differed from previously published grids, in that the new grid showed; (1) no predicted postnatal weight loss among neonates in categories<900 g birth weight, (2) less initial weight loss among neonates 900-2500 g, (3) fewer days to regain birth weight among neonates<or=2000 g, and (4) fewer days to gain 100 and 300 g above birth weight in neonates<or=1500 g.

SPECULATION

For charting serial weights of LBW neonates in the NICU the new grid may be a useful standard.

Human milk supplementation for preterm infants

Nutrition support of the premature infant must be designed to compensate for metabolic and gastrointestinal immaturity, immunologic compromise, and associated medical conditions. The beneficial effects of human milk extend to the feeding of premature infants. However, nutritional concerns arise because the quantity of nutrients in human milk may not meet the great nutrient needs of the premature infant born weighing less than 1500 g. Human milk fortifiers are available to provide optimum nutrition. This review summarizes the benefits and limitations of human milk for the premature infant.

Growth, efficacy, and safety of feeding an iron-fortified human milk fortifier

OBJECTIVE

Survival rates for preterm infants who weigh between 501 and 1500 g at birth have continued to improve over time. In response to this continuing decrease in birth weight of surviving preterm infants, Enfamil Human Milk Fortifier has recently been reformulated to meet the nutritional requirements of these smaller, more rapidly growing infants. It now provides an increased protein level of 1.1 g/58 kJ, a decreased carbohydrate level of 0.2 g/58 kJ, and a combined linoleic and alpha-linolenic fatty acid content of 157 mg/58 kJ. As these very small preterm infants have an increased requirement for dietary iron, the fortifier has been supplemented with 1.44 mg/58 kJ of iron, an amount of iron similar to that provided in a typical iron-fortified term infant formula. An iron-fortified product obviates the need for administration of an iron supplement, a hyperosmolar-inducing intervention. The purpose of this prospective, double-blind, randomized, controlled study was to evaluate growth, safety, and efficacy in a population of very low birth weight (VLBW) preterm infants who received human milk fortified with either the reformulated iron-fortified powdered human milk fortifier test product (HMF-T) or a powdered commercially available human milk fortifier control product (HMF-C).

METHODS

Infants who weighed < or =1500 g, had a gestational age < or =33 weeks postmenstrual age, and had an enteral intake of at least 100 mL/kg per day of unfortified human milk were stratified by gender and birth weight and randomized to receive HMF-T or HMF-C product from study day 1 to study day 28, hospital discharge, or the termination of human milk feedings, whichever came first. Unless medically indicated, investigators were not to administer iron supplements from study days 1 to 14. Infants were assessed serially for growth; enteral and parenteral intake; serum chemistry and hematologic values; clinical histories, including the administration of blood transfusions; feeding tolerance; respiratory outcomes; and morbidities, including adverse events.

RESULTS

Of the 181 participating infants in this study, 96 received HMF-T and 85 received HMF-C. At randomization, there were no significant differences in infant characteristics between the fortifier groups. The percentage of participants who remained in the study for 28 days was similar between fortifier groups (57% HMF-T, 46% HMF-C). For both fortifier groups, the most frequent reasons for discontinuing the study before study day 28 were unavailability of human milk and hospital discharge. Rate of weight gain was similar between the fortifier groups (17.5 +/- 0.53 g/kg per day for HMF-T and 17.3 +/- 0.59 g/kg per day for HMF-C). Mean achieved weight, length, and head circumference were comparable between groups across the 28-day study period. Total protein intake from enteral and parenteral nutrition was significantly greater for the HMF-T fortifier group; however, this difference did not result in any difference in growth between the 2 fortifier groups. An analysis of the growth and energy intake data of a subset of the intent-to-treat population who adhered more strictly to the study feeding protocol yielded results similar to those seen for the intent-to-treat population. There were no clinically significant differences in the results of laboratory studies between the groups at study days 0, 14, and 28. Anemia of prematurity was prevalent in both study groups; by study day 28, median hematocrit levels were 27.0% (interquartile range [IQR]: 24.0%-29.6%) for the HMF-T group and 26.0% (IQR: 24.0%-31.0%) for the HMF-C group. Median ferritin levels were 77.0 ng/mL (IQR: 37-155 ng/ml) for HMF-T and 92.0 ng/mL (IQR: 33-110 ng/mL) for HMF-C. There were no significant differences between the study fortifier groups in regard to the receipt of medically indicated iron supplements on or before study day 14 or in the administration of blood transfusions before study day 0 or from study days 0 through 14. However, from study day 15 to study day 28, fewer HMF-T infants (n = 12) required a blood transfusion than did HMF-C infants (n = 20). Although the higher levels of iron in the HMF-T fortifier (1.44 mg vs 0.35 mg for HMF-C per 4 packets of powdered fortifier) did not prevent anemia per se, it did reduce the frequency of one of the most serious outcomes of anemia: the need for a blood transfusion. There was no statistically significant difference between fortifier groups in regard to feeding tolerance. Rates of suspected sepsis (26% HMF-T vs 31% HMF-C) and confirmed sepsis (5% HMF-T, 7% HMF-C) were low as were the rates of suspected necrotizing enterocolitis (NEC; 6% HMF-T and 5% HMF-C) and confirmed Bell's stage 2 or more NEC (1% HMF-T and 1% HMF-C). There were no statistically significant differences between the study fortifier groups in regard to the incidence of confirmed and suspected sepsis and NEC.

CONCLUSION

Both human milk fortifiers studied are safe, are well tolerated, and facilitate comparable good growth; however, using the iron-fortified product may reduce the need for blood transfusions in VLBW infants. The similar low rates of suspected and confirmed NEC and sepsis seen in both fortifier groups in this study refutes the premise that the inclusion of iron in fortifiers will increase the incidence of sepsis and NEC. Indeed, the incidence for NEC and sepsis for both groups in this study was lower than is reported for VLBW infants and similar to that seen for infants who are fed human milk.

Safety and Efficacy of Human Milk Fortification for Very-Low-Birth-Weight Infants

For full-term infants in the first 6 months of life, exclusive breastfeeding remains the nutritional standard for calcium intake. However, unsupplemented human milk does not meet the nutritional requirements for growth of the very-low-birthweight (<1500 g) infant. Methods for human milk fortification have been evaluated, and recent studies have demonstrated the safety of these fortifiers.

Nutrition of very low birth weight infants fed human milk with or without supplemental trace elements: a randomized controlled trial

BACKGROUND

Very low birth weight infants (<1500 g) have high nutritional needs. Deficiencies of minerals, trace elements (especially zinc) may develop as a result of rapid growth, low body stores and low content of these substances in human milk We hypothesized that fortification of human milk might prevent deficiencies.

METHODS

Prospective, randomized trial to evaluate mineral, trace element, thyroid status and growth of infants fed human milk fortified with different amounts of calcium, phosphorus and protein, with (BMF) or without (FM 85) trace elements. Sixty-two infants, 1000 to 1499 g birth weight, were randomized. Minerals and trace elements in serum, red blood cells and human milk and alkaline phosphatase activity, TSH, T4 and FT4 in serum were measured once until the fifth day and at 3 and 6 weeks of life. Clinical course and anthropometric measurements were recorded.

RESULTS

Intake of zinc, copper, manganese, calcium, phosphorus and magnesium was higher in the BMF group (P < 0.001). Serum zinc concentrations <0.49 mg/L occurred in 12% of the FM 85 group and 7% of the BMF group at 6 weeks (not significant). Median alkaline phosphatase activity was 436/379 IU/L in the FM 85/BMF group at 6 weeks (P < 0.01). The FM 85 group showed a higher weight gain (P < 0.05), possibly because of higher caloric (P < 0.01) and protein intake (P < 0.05) at 3 weeks.

CONCLUSIONS

Zinc deficiency was rare. Elevated intake of calcium, phosphorus and zinc was associated with lower serum alkaline phosphatase activity but did not influence serum zinc concentration.

Multicomponent fortified human milk for promoting growth in preterm infants

BACKGROUND

For term infants, human milk provides adequate nutrition to facilitate growth, as well as potential beneficial effects on immunity and the maternal-infant emotional state. However, the role of human milk in premature infants is less well defined as it contains insufficient quantities of some nutrients to meet the estimated needs of the infant. Observational studies have suggested that infants fed formula have a higher rate of growth than infants who are breast fed. However, there are potential short term and long term benefits from human milk. Commercially-produced multicomponent fortifiers provide additional nutrients to supplement human milk (in the form of protein, calcium, phosphate, and carbohydrate, as well as vitamins and trace minerals).

OBJECTIVES

The main objective was to determine if addition of multicomponent nutritional supplements to human milk leads to improved growth, bone metabolism and neurodevelopmental outcomes without significant adverse effects in premature infants.

SEARCH STRATEGY

Searches were made of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2, 3003), MEDLINE (searched August 29, 2003), previous reviews including cross references, abstracts, conferences and symposia proceedings, expert informants, journal handsearching mainly in the English language.

SELECTION CRITERIA

All trials utilising random or quasi-random allocation to supplementation of human milk with multiple nutrients or no supplementation in premature infants within a nursery setting were eligible.

DATA COLLECTION AND ANALYSIS

Data were extracted using the standard methods of the Cochrane Collaboration and its Neonatal Review Group, with separate evaluation of trial quality and data extraction by each author and synthesis of data using relative risk and weighted mean difference.

MAIN RESULTS

Supplementation of human milk with multicomponent fortifiers is associated with short term increases in weight gain, linear and head growth. There is no effect on serum alkaline phosphatase levels; it is not clear if there is an effect on bone mineral content. Nitrogen retention and blood urea levels appear to be increased. There are insufficient data to evaluate long term neurodevelopmental and growth outcomes, although there appears to be no effect on growth beyond one year of life. Use of multicomponent fortifiers does not appear to be associated with adverse effects, although the total number of infants studied and the large amount of missing data reduces confidence in this conclusion. Blood urea levels are increased and blood pH levels minimally decreased, but the clinical significance of this is uncertain.

REVIEWER'S CONCLUSIONS

Multicomponent fortification of human milk is associated with short-term improvements in weight gain, linear and head growth. Despite the absence of evidence of long-term benefit and insufficient evidence to be reassured that there are no deleterious effects, it is unlikely that further studies evaluating fortification of human milk versus no supplementation will be performed. Further research should be directed toward comparisons between different proprietary preparations and evaluating both short-term and long-term outcomes in search of the "optimal" composition of fortifiers.

Calcium and bone health in infants

Osteopenia, rickets, and fractures from nutrient deficiencies can occur during infancy, particularly in preterm infants. Bone mass accretion during the first year of life is equal to or greater than that achieved at any other stage of life, including adolescence. Optimizing calcium and bone status during infancy can have immediate benefits in maintaining calcium homeostasis and preventing disturbances in bone mineralization and can provide long-term benefits by helping infants to later reach their maximum genetic potential for peak bone mass, a prerequisite for the prevention of osteoporosis and its complications. Dietary calcium requirements during infancy generally reflect the need to achieve normal growth and bone mineralization because 99 percent of total body calcium is present in the skeleton. Knowledge of physiologic factors that determine infant calcium requirements and the bioavailability of calcium from various dietary sources is important to ensuring bone health during infancy. Also key are the practical issues related to optimizing calcium nutriture in infants born at term and prematurely.

Nutrition in the neonatal intensive care unit: how do we reduce the incidence of extrauterine growth restriction?

Extrauterine growth restriction is a major clinical problem for prematurely born neonates, especially critically ill preterm neonates, and malnutrition in the neonatal intensive-care unit remains common. There are numerous perceived risks to initiation of adequate nutritional support. How many of these factors pose a real risk to health outcomes is less clear. Current nutritional support does not prevent extrauterine growth restriction and the consequences of malnutrition are both acute and delayed. Our clinical approach to providing nutritional support impacts neonatal morbidity and long-term neuro developmental outcomes. While more and better evidence is needed to help guide best practices, this gap should not prevent neonatologists from using the observations in this review to improve their current practice. There is evidence that changes in nutritional support can have a positive influence on growth. These include early administration of intravenous amino acids and lipids, minimal enteral nutrition, and supplemented formula and human milk. Simply recognizing the degree of growth failure by monitoring weight and focusing on the accruing deficit should encourage clinicians to increase nutritional support to enhance recovery growth. Continued research is needed to define the efficiency of early feeding, more rapid advancements in nutritional support, protein needs, the optimal composition of breast-milk supplements, the etiology of necrotizing enterocolitis, and perhaps most importantly, the health consequences of extrauterine growth restriction.

[Postnatal growth delay in 27 to 33 week premature infants: frequency and risk factors. Retrospective study of 161 cases]

The optimization of the nutrition of very low birth weight premature neonates has become a major concern given the improvement in survival for these children. The goal of the recommended nutritional intakes is to reach a quantitative and qualitative growth similar to the in utero growth. The objectives of this study were to analyze the anthropometric data at birth and near term in a cohort of premature neonates with birth weight appropriate for gestational age and to try to determine risk factors of postnatal hypotrophy.

POPULATION AND METHODS

We conducted a retrospective study over three years (1998-2001) in the neonatology unit of the Armand Trousseau Children's Hospital, Paris, France. The inclusion criteria was a gestational age under 33 weeks with birth weight appropriate for gestational age. Data were collected at admission, during hospitalisation and at discharge and a standardised form was filled for each child. We defined postnatal hypotrophy (PNH) as an hypotrophy at discharge (weight < 10(th) centile according to the Audipog reference curve) in neonates with birth weight appropriate for gestational age.

RESULTS

One hundred and sixty one neonates were included. Eighty two had PNH. In univariate analysis, factors significantly associated with PNH were: birth weight, gestational age, length of hospitalisation, the occurrence of nosocomial infection, of enteropathy, preeclampsia, neonatal asphyxia and antenatal corticoid treatment. In multivariate analysis, risk factors of PNH were: low birth weight, low gestational age and the occurrence of nosocomial infection.

CONCLUSION

Our study shows that half of the appropriate for gestational age premature neonates were hypotrophic near term. The causes may be various: nutrition is not optimal and intercurrent factors may play a major role such as nosocomial infection.

Site of care influences breastmilk feedings at NICU discharge

OBJECTIVE

To determine if site of care influences rates of breastmilk use in neonatal intensive care units (NICUs).

STUDY DESIGN

Subjects included all admissions to 124 NICUs between 1/1/1999 and 12/31/2000 who were subsequently discharged home. We reviewed discharge feeding data collected during the routine provision of care, and used stepwise logistic regression analysis to identify which factors were independently associated with a neonate being discharged on some breastmilk versus none.

RESULTS

We studied 42,891 neonates; 21,327 (49.7%) were sent home receiving some breastmilk and 21,564 (50.3%) were not. The significant variables associated with being discharged on breastmilk were more mature gestational age, white race, maternal age, parents being married, and site of care. Site of care remained significant even when adjusted for other variables.

CONCLUSION

Neonates admitted to NICUs are often discharged on feedings that do not include breastmilk. Beyond previously identified risk factors, site of care significantly influences this occurrence.

Effects of human milk fortification on morbidity factors in very low birth weight infants

BACKGROUND

The use of human milk as a sole source of nutrients for preterm infants has been the subject of debate in recent years. We studied the morbidity factors associated with hospitalization of very low birth weight (VLBW) infants fed human milk with and without fortification.

PATIENTS AND METHODS

One hundred VLBW infants were randomly assigned to two groups with stratification for gestation and weight. The control group (n-50; mean birth weight 1239+/-186 g and mean gestation 29.3+/-2.1 wks) was fed human milk only, and in the fortifier group (n=50; mean birth weight 1245+/-191 g and mean gestation 29.5+/-2.1 wks), human milk was enriched with a fortifier after the babies reached a volume of 140 mL/kg/day by the enteral route. Weight was measured twice weekly, biochemical indices of nutritional and bone status and serum electrolytes were obtained weekly, and clinical evidence for sepsis, necrotizing enterocolitis and feeding intolerance was assessed regularly until infants were discharged.

RESULTS

Hospital stay was less than 45 days in the majority (94%) of the babies in the fortifier group, whereas the majority (66%) of the babies in the control group stayed for more than 45 days (P<0.01). Low serum phosphorus and raised alkaline phosphate levels were seen more frequently in the control group without fortification (p<0.01), as weel as hyponatremia (P<0.01), late metabolic acidosis of prematurity (P<0.01) and culture-proven sepsis (p<0.05). There was no significant difference in the occurrence of necrotizing enterocolitis between the two groups (P>0.05).

CONCLUSION

Human milk fortification has beneficial effects on the growth of VLBW infants and decreases hospital stay and morbidity associated with prematurity and very low birth weight, with economic and psychological benefits for the parents.

Mothers' milk feedings in the neonatal intensive care unit: accuracy of the creamatocrit technique

OBJECTIVE

To establish the accuracy of the creamatocrit (CRCT) for estimating lipid and calories in a heterogeneous sample of own mothers' milk (OMM) in the neonatal intensive care unit (NICU), using a hematocrit reader, rather than fine vernier calipers.

STUDY DESIGN

In this blinded study, CRCT techniques were performed on 32 fresh OMM samples (7 foremilk, 12 hindmilk, 13 composite milk) that were also analyzed for total lipid and caloric concentration.

RESULTS

Mean lipid and caloric concentrations for the OMM samples were 50.87 g/l (28.3-86.5) and 703.96 kcal/l (477.2-1183.6), respectively. Results revealed a stronger linear relationship between CRCT and total lipid (r=0.94; p<0.001) than between CRCT and caloric density (r=0.76; p<0.001).

CONCLUSION

The CRCT, using a hematocrit reader, is an accurate, inexpensive, and useful technique for estimating the lipid and caloric concentration of individual OMM samples in the NICU. The variability in lipid and calories in these 32 OMM samples underscores the utility of this technique.

Intersite differences in weight growth velocity of extremely premature infants

OBJECTIVE

To explain differences in weight growth velocity of extremely premature infants among 6 level III neonatal intensive care units (NICUs).

METHODS

In 6 NICUs, we studied 564 infants, stratified by gestational age (GA), who were first admissions, survivors, <30 weeks' GA at birth, and in the NICU at least 16 days. Case mix (eg, birth weight, GA, race, illness severity, prenatal steroids), exposure to medical practices/complications (eg, respiratory support, postnatal steroids, necrotizing enterocolitis, infection), and nutritional intake (kcal/kg/d and protein in g/kg/d) were collected and used to predict weight growth velocity between day 3 and day 28 (or discharge, if transferred early) in multiple linear regression models.

RESULTS

Weight growth velocities varied significantly among the 6 NICUs. Adjustment for case mix and medical factors explained little of this variability, but additional control for calorie and especially protein intake accounted for much of the intersite variability. For the average infant, adjusted growth velocity ranged from 10.4 to 14.3 g/kg/d among the sites studied. The final predictive model, including case mix and medical and nutritional factors, explained 53% of the overall variance in growth velocity. Prolonged (> or =15 days) exposure to postnatal steroids and greater severity of illness both decreased growth velocity. The model predicted that adding 1 g/kg/d protein to the mean intake for our sample would increase growth by 4.1 g/kg/d.

CONCLUSIONS

Variation in nutrition explained much of the difference in growth among the NICUs studied. Mean intake of calories and protein failed to meet recommended levels, and the average growth in only 1 NICU approximated intrauterine growth standards. Increasing nutritional intake into the recommended ranges, in particular of protein, may increase growth of extremely premature infants up to or above intrauterine rates.

Enhanced weight gain in preterm infants receiving lactase-treated feeds: a randomized, double-blind, controlled trial

OBJECTIVE

To evaluate whether lactase-treated preterm feeds enhance weight gain and feeding tolerance in premature infants.

STUDY DESIGN

Prospective, double-blind, randomized, controlled trial involving 130 infants (26-34 weeks postconceptual age). The primary outcome variable was weight gain (g per day). Other outcome measures included gains in length and head circumference, biochemical indexes of nutritional status, feeding intolerance, and incidence of necrotizing enterocolitis.

RESULTS

On study day 10, weight gain (mean +/- SEM) of the treatment group was significantly greater (P <.05) than that of the control group (20.4 +/- 1.8 g/day vs 15.5 +/- 1.6 g/day). By study end, no significant difference in weight gain between treatment and control groups was observed. The difference in serum albumin level was significant at study day 14, with a value of 29.3 +/- 0.6 g/L in the treatment group compared with 27.1 +/- 0.4 g/L in the control group (P <.01). There were no significant differences in caloric intakes, length gain, head circumference gain, feeding intolerance, and incidence of necrotizing enterocolitis.

CONCLUSIONS

Weight gain may be enhanced during the period of low functional lactase activity of prematurity by addition of lactase to preterm feeds. No adverse effects on feeding tolerance resulted from this treatment.

Effects of human milk fortification on morbidity factors in very low birth weights infants

BACKGROUND

The use of human milk as a sole source of nutrients for preterm infants has been the subject of debate in recent years. We studied the morbidity factors associated with hospitalization of very low birth weight (VLBW) infants fed human milk with and without fortification.

PATIENTS AND METHODS

One hundred VLBW infants were randomly assigned to two groups with stratification for gestation and weight. The control group (n=50; mean birth weight 1239+/-186 g and mean gestation 29.3+/-2.1 wks) was fed human milk only, and in the fortifier group (n=50; mean birth weight 1245+/-191 g and mean gestation 29.5+/-2.1 wks), human milk was enriched with a fortifier after the babies reached a volume of 140 mL/kg/day by the enteral route. Weight was measured twice weekly, biochemical indices of nutritional and bone status and serum electrolytes were obtained weekly, and clinical evidence for sepsis, necrotizing enterocolitis and feeding intolerance was assessed regularly until infants were discharged.

RESULT

Hospital stay was less than 45 days in the majority (94%) of the babies in the fortifier group, whereas the majority (66%) of the babies in the control group stayed for more than 45 days (P<0.01). Low serum phosphorus and raised alkaline phosphatase levels were seen more frequently in the control group without fortification (P<0.01), as well as hyponatremia (P<0.01), late metabolic acidosis of prematurity (P<0.01) and culture-proven sepsis (P<0.05). There was no significant difference in the occurrence of necrotizing enterocolitis between the two groups (P>0.05).

CONCLUSION

Human milk fortification has beneficial effects on the growth of VLBW infants and decreases hospital stay and morbidity associated with prematurity and very low birth weight, with economic and psychological benefits for the parents.

The use of human milk for premature infants

Various methods have been reported and used clinically to augment the nutrient supply for human milk-fed premature infants. These methods include specialized maltinutrient powdered mixtures (fortifiers), complete liquid formulas designed to be mixed with human milk, complete powdered formulas to be mixed with human milk, and alternate feeding of human milk and preterm formula. Although the optimum nutrition of premature infants is unknown, data are accumulating to suggest that human milk, fortified with additional nutrients, is appropriate for tube-fed infants. The use of fortified human milk typically provides premature infants adequate growth, nutrient retention, and biochemical indices of nutritional status when fed at approximately 180 mL/kg/d compared with unfortified human milk. Data are needed to determine the precise quantity of nutrients to be added as supplements. Nutrient interactions have not been explored in detail. Although large quantities of calcium seem to be needed, the exogenous calcium may affect fat absorption adversely. Manipulation of milk may affect the intrinsic host-defense properties of the milk. Compared with preterm formula, the feeding of fortified human milk may provide significant protection from infection and NEC. Lastly, the potential stimulation of an enteromammary pathway through skin-to-skin contact provides species-specific antimicrobial protection for premature infants. Several of these areas require additional exploration. Thus, for premature infants, neonatal centers should encourage the feeding of fortified human milk, together with skin-to-skin contact, as reasonable methods to enhance milk production while potentially facilitating the development of an enteromammary response.