Does Human Milk Modulate Body Composition in Late Preterm Infants at Term-Corrected Age?

Formula with large, milk phospholipid-coated lipid droplets in late-moderate preterm infants: a double-blind RCT

BACKGROUND

Limited evidence exists on the preferred feeding method when breastfeeding is not possible in late and moderate preterm (LMPT) infants. This RCT evaluates growth, safety, and tolerance of a concept infant formula (IF) with large, milk phospholipid-coated lipid droplets enriched in dairy lipids in LMPT infants with primary objective to demonstrate non-inferiority of daily weight gain from randomization to 3 months corrected age compared to a standard IF.

METHODS

LMPT infants were randomized before or around term equivalent age to either the concept (n = 21) or standard IF (n = 20). Forty-one breastfed (BF) infants served as reference.

RESULTS

Due to unintended low recruitment, non-inferiority in daily weight gain could not be demonstrated for the Concept compared to the Control group, but was compared to the BF group. Other outcomes were similar between the formula groups, except for an apparent larger head circumference gain in the Concept group. No apparent differences in growth and body composition outcomes were observed between the Concept and BF reference groups.

CONCLUSION

This small-scale study suggests the concept IF is a safe alternative for parents who choose IF to feed their LMPT infant. Larger trials are needed to better determine impacts on head growth or body composition.

IMPACT

In a small group of late and moderate preterm infants, growth from randomization until 3 months corrected age of infants fed with a concept infant formula with large, milk phospholipid-coated lipid droplets was not -significantly different from infants fed a standard infant formula. Infants in the Concept group had non-significant larger gain in head circumference compared to the Control group; larger trials are needed to confirm this finding. Both formulas were well-tolerated, with no differences in adverse events. The concept formula is potentially a safe alternative for parents of moderate to late preterm infants who choose to use formula milk.

Growth and body composition of infants born moderate-to-late preterm fed a protein- and mineral-enriched postdischarge formula compared with a standard term formula until 6 months corrected age, a randomized controlled trial

BACKGROUND

Infants born moderate-to-late preterm (i.e., 32 wk-35 wk 6 d gestation) are, analogous to those born very preterm, at risk of later obesity, hypertension, and diabetes. Appropriate early life nutrition is key for ensuring optimal growth and body composition, thereby mitigating potential cardiometabolic risks.

OBJECTIVES

We aimed to compare growth and body composition between infants born moderate-to-late preterm fed isocaloric but protein- and mineral-enriched postdischarge formula (PDF) or standard term formula (STF) until 6 mo corrected age (CA; i.e., after term equivalent age [TEA]).

METHODS

After enrollment (≤7 d postpartum), infants received PDF if (fortified) mother's own milk (MOM) was insufficient. At TEA, those receiving >25% of intake as formula were randomized to either continue the same PDF (n = 47) or switch to STF (n = 50); those receiving ≥75% of intake as MOM (n = 60) served as references. At TEA and 6 mo CA, we assessed anthropometry and body composition using both dual-energy x-ray absorptiometry (DXA) and air displacement plethysmography (ADP).

RESULTS

Feeding groups had similar gestational age (median [25th percentile;75th percentile]: 34.3 [33.5; 35.1] wk), birthweight (mean ± standard deviation [SD]: 2175 ± 412 g), anthropometry, and body composition at TEA. At 6 mo CA, infants fed PDF had slightly, but significantly, greater length (67.6 ± 2.5 and 66.9 ± 2.6 cm, P < 0.05) and larger head circumference (43.9 ± 1.3 and 43.4 ± 1.5 cm, P < 0.05) compared to infants fed STF. Also, infants fed PDF had higher lean mass (LM) and bone mineral content estimated by DXA (4772 ± 675 and 4502 ± 741 g; 140 ± 20 and 131 ± 23 g, respectively; P < 0.05). ADP estimates, however, were not statistically different between feeding groups.

CONCLUSIONS

Infants born moderate-to-late preterm demonstrated modest increases in length, head circumference, LM, and bone mineral content when fed PDF compared to STF for 6 mo after TEA. This trial was registered at the International Clinical Trial Registry Platform as NTR5117 and NTR NL4979.

State of the Science on the Benefits of Human Milk for Hospitalized, Vulnerable Neonates

Research on human milk has increased dramatically in recent years. The purpose of this review is to describe the literature on the health benefits of human milk for hospitalized, vulnerable neonates. PubMed, CINAHL, and Embase were searched for research articles reporting the health outcomes of hospitalized neonates who were exposed to human milk. Human milk, particularly a mother's own milk, has the potential to reduce the risk of death and the risk and severity of necrotizing enterocolitis, infection, retinopathy of prematurity, bronchopulmonary dysplasia, intraventricular hemorrhage, kidney disease, and liver disease. Dose and timing of human milk is important, with more human milk and earlier introduction having a greater impact on health. When a mother's own milk is not available, donor human milk provides benefits over infant formula.

The weight for length in late preterm infants assessed with bioelectrical impedance is positively associated with anthropometric variables

INTRODUCTION

The fat mass (FM) is greater in late preterm than full term infants at 1 month post birth, which may be an additional risk factor for metabolic syndrome in adulthood.

OBJETIVES

To evaluate body composition (BC) in late preterm infants using bioelectrical impedance analysis (BIA) to determine which anthropometric parameters are associated with BC. Our hypothesis was that weight-for-length is associated with the length-normalized fat mass index (FMI) at 1 year of life.

MATERIALS AND METHODS

We carried out a prospective cohort study in 2 groups: late preterm infants and full term infants. We obtained BC data by BIA. We calculated the fat mass (FM), FMI, fat-free mass (FFM) and length-normalized fat-free mass index (FFMI) at 1, 6 and 12 months of life. After, we assessed the association of the FMI with anthropometric parameters using multiple linear regression analysis.

RESULTS

The study included 97 late preterm and 47 full term infants, although at 12 months of life, the BC assessment was performed on 66 and 33 infants, respectively. Late preterm infants, compared to full term infants, had a higher FFM at 1 month (4013 vs 3524 g), a higher weight velocity at 6 months (5480 g versus 4604 g) and a lower FFM (7232 vs 7813 g) and FFMI (12.55 vs 13.26) at 12 months of life. The multivariate regression analysis showed that the weight-for-length z-core at 12 months was positively associated with the FMI at 12 months in all infants.

CONCLUSION

The weight-for-length z-score at 12 months is strongly associated with the FMI at 1 year of life. Further studies are needed to investigate whether an increment in this anthropometric parameter may modulate the risk of chronic diseases.

Efficacy of a breastfeeding support education program for nurses and midwives: a randomized controlled trial

BACKGROUND

Nutritional support influences the growth and development of late preterm infants (LPIs) and their long-term health status. However, healthy LPIs have a shorter hospital stay and may not receive adequate care after discharge. In this study, we developed and evaluated the effectiveness of an educational program for nurses and midwives to enable them to support breastfeeding of healthy LPIs.

METHODS

A randomized controlled trial was conducted in Japan from July 2018 to April 2019. The participant pool consisted of nurses and midwives working at midwiferies and obstetric centers in Tokyo, Japan. A total of 395 candidates were recruited for participation across 79 facilities. The final participants were assigned to two groups: the breastfeeding support for LPIs program (BSLPI group; n = 36) or the non-technical skills program (NTS group; n = 33). The measures included the Self-Efficacy of Breastfeeding Support scale (SBS), the Social Skills in Nursing Interactions with Mothers (SS) scale, and the Knowledge and Skills Necessary for Breastfeeding Support for LPIs test (K-S). Scores for each measure were collected before, after, and one-month after the intervention. Repeated-measures ANOVA was used to identify differences (main effects) according to program (BSLPI and NTS) and time (before, immediately after, and one month after intervention).

RESULTS

All 69 participants attended the program. Main effects of the program were observed only for K-S scores (F[1,58] = 78.57, p = 0.01). No significant differences were found for SBS (F[1,58] = 0.63, p = 0.43) or SS scores (F[1,58] = 1.51, p = 0.23).

CONCLUSIONS

Participation in the BSLPI was related to improved breastfeeding support knowledge and skills but was not related to improvements in nurses' self-efficacy or social skills.

TRIAL REGISTRATION

Registered 12 December 2018, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000040145 (UMIN: UMIN000035227).

Postnatal growth of small for gestational age late preterm infants: determinants of catch-up growth

BACKGROUND

Failure to recover growth is a risk reported in late preterm population. This study aimed to evaluate the auxological outcome of late preterm infants and identify factors associated with failure to recover growth.

METHODS

We enrolled late preterm infants with birth weight ≤10th percentile, followed up at High-Risk Infant Follow-up Service. We collected data at birth and at follow-up visits. A logistic regression analysis was performed to assess variables independently associated with growth failure.

RESULTS

The population consisted of 175 preterms. The percentage of children showing no weight recovery was 34% at 36 months. At logistic regression analysis, infants who had not regained weight at 12 months had a higher risk of not regaining weight even at 36 months. The same risk factor was highlighted for length catch-up growth. Moreover, infants fed any human milk at discharge were protected from not achieving both weight and length catch-up growth at 36 months.

CONCLUSION

These results indicate that children born late preterm and small for gestational age could fail to recover weight and stature growth in the first 36 months. The protective effect of human milk on failure to thrive highlights the importance of promoting breastfeeding in this population.

IMPACT

A significant number of SGA late preterms show a failure to recover weight and statural growth. Having experienced intrauterine growth restriction is associated with a greater chance of achieving statural catch-up growth. Being born singleton represents a risk factor for slower weight and height growth velocity. Breastmilk has a protective effect on failure to recover adequate weight and length in preterm SGA infants. This finding highlights the importance of promoting breastfeeding in this population.

Impact of Breastfeeding on Low Birthweight Infants, Weight Disorders in Infants, and Child Development

Infancy has been proven as the best time to improve health outcomes for the later stage of life. The composition of human breast milk has evolved over millennia to support and maintain the infant's life during the early years of life. To achieve life-sustaining effects, human breast milk is packed with fats, proteins, carbohydrates, and a wide range of bioactive compounds such as immunoglobulins, lactoferrin, and cytokines. The immunological compounds in breast milk have been shown to curtail gastrointestinal tract infections, respiratory tract infections, hospital admissions, acute otitis media, allergic reactions, and urinary tract infections. Although breastfeeding causes newborns to gain less weight at the beginning of their lives than formula milk does, breast milk improves body composition by low adiposity. A higher adipose deposition in infants is linked with an increased risk of child obesity in the future. Due to significant health benefits, the World Health Organization (WHO) recommends initiating breastfeeding within one hour after birth and continuing for at least six months. Breastfeeding has emerged as a superior source of nutrition that can promote healthy physiological and cognitive development and protect against disease challenges in low birthweight infants. This review summarizes potential evidence that highlights the potential health impact of breast milk in low birthweight infants.

Sex differences in preterm nutrition and growth: the evidence from human milk associated studies

Sexual dimorphism of the fetus manifests itself even during pregnancy. Preterm births are more common in pregnancies with male fetuses. Intrauterine and postnatal growth nomograms are sex-specific. The human milk composition in term infants appears to be sex-specific. Early nutrition has sex-specific effects and neurodevelopmental outcomes. A large same-sex twin study suggests that a mother's own milk (MOM) provides sex-specific growth advantages probably related to the calibration of a mother's milk based on her newborn's sex. Formula composition does not vary with infant sex, which may be one reason why body composition data favors the use of MOM over formula. However, given the lack of data on this subject, we need more detailed information on how the sex-specific micronutrients in MOM influence infant well-being. We also need more information to ascertain the sex differences in infants' macronutrient requirements, such as whether preterm females have higher fat requirements and preterm males have higher protein requirements for optimal growth and neurodevelopmental outcomes. This information may also influence milk banking and the use of donor human milk (DBM). Further research may help us determine if we should provide sex-specific DBM to those preterm infants who cannot get their MOM.

Energy Expenditure, Protein Oxidation and Body Composition in a Cohort of Very Low Birth Weight Infants

The nutritional management of preterm infants is a critical point of care, especially because of the increased risk of developing extrauterine growth restriction (EUGR), which is associated with worsened health outcomes. Energy requirements in preterm infants are simply estimated, so the measurement of resting energy expenditure (REE) should be a key point in the nutritional evaluation of preterm infants. Although predictive formulae are available, it is well known that they are imprecise. The aim of our study was the evaluation of REE and protein oxidation (Ox) in very low birth weight infants (VLBWI) and the association with the mode of feeding and with body composition at term corrected age. Methods: Indirect calorimetry and body composition were performed at term corrected age in stable very low birth weight infants. Urinary nitrogen was measured in spot urine samples to calculate Ox. Infants were categorized as prevalent human milk (HMF) or prevalent formula diet (PFF). Results: Fifty VLBWI (HMF: 23, PFF: 27) were evaluated at 36.48 ± 0.85 post-conceptional weeks. No significant differences were found in basic characteristics or nutritional intake in the groups at birth and at the assessment. No differences were found in the REE of HMF vs. PFF (59.69 ± 9.8 kcal/kg/day vs. 59.27 ± 13.15 kcal/kg/day, respectively). We found statistical differences in the protein-Ox of HMF vs. PFF (1.7 ± 0.92 g/kg/day vs. 2.8 ± 1.65 g/kg/day, respectively, p < 0.01), and HMF infants had a higher fat-free mass (kg) than PFF infants (2.05 ± 0.26 kg vs. 1.82 ± 0.35 kg, respectively, p < 0.01), measured with air displacement plethysmography. Conclusion: REE is similar in infants with a prevalent human milk diet and in infants fed with formula. The HMF infants showed a lower oxidation rate of proteins for energy purposes and a better quality of growth. A greater amount of protein in HMF is probably used for anabolism and fat-free mass deposition. Further studies are needed to confirm our hypothesis.

Preterm infant nutrition and growth with a human milk diet

Human milk is the preferred enteral diet for preterm infants. It provides macronutrients, micronutrients, and bioactive factors that support physical growth and neurodevelopment. Challenges of the human milk diet include the variability in its composition and a need for fortification to mirror placental nutrient delivery and prevent extrauterine growth restriction. Various strategies exist to attain target nutrient provision and optimize growth, including leveraging new technology for point-of-care human milk analysis. When maternal milk is unavailable or in short supply, pasteurized donor human milk is the preferred alternative. Infants fed donor milk may have slower weight gain than those fed exclusively maternal milk or formula, whereas infants fed fortified maternal milk have similar weight gain to preterm formula-fed infants. Future directions include more rigorous characterization of the variation in human milk, further investigation of the clinical benefits of non-nutrient bioactive factors in milk, and novel approaches to optimize fortification.

Human Milk Feeding and Preterm Infants' Growth and Body Composition: A Literature Review

Preterm infants may show a higher risk of adverse health outcomes, such as the development of metabolic syndrome and cognitive impairment. The most recent evidence highlights that nutrition, body composition development, and early postnatal growth may play a role in the programming of these processes. Human milk feeding has been recommended as the natural feeding for preterm infants and as a cost-effective strategy for reducing disease and economic burden. Considering that the postnatal growth retardation and aberrant body composition shown by preterm infants at the time of hospital discharge still remain important issues, we performed a literature review, aiming to provide an update about the effect of human milk feeding on these processes. On the basis of our findings, human milk feeding in preterm infants, although related to a slower weight gain than formula feeding, is associated with a better recovery of body composition through the promotion of fat-free mass deposition, which may ultimately lead to better metabolic and neurodevelopmental outcomes. Promotion and support of human milk feeding should be considered a priority in preterm infants' care.

Adiposity and Fat-Free Mass of Children Born with Very Low Birth Weight Do Not Differ in Children Fed Supplemental Donor Milk Compared with Those Fed Preterm Formula

BACKGROUND

Many mothers of very-low-birth-weight (VLBW) infants (<1500 g) are unable to provide sufficient breast milk, and supplemental pasteurized donor human milk (donor milk) or preterm formula is required. The composition of donor milk differs from that of mother's milk and infants fed with donor milk often exhibit slower growth during hospitalization. The long-term impact of nutrient-enriched donor milk on growth, body composition, or blood pressure is unknown.

OBJECTIVE

We aimed to determine the effects of nutrient-enriched donor milk compared with preterm formula on growth, body composition, and blood pressure of children born preterm and with VLBW. Associations with in-hospital mother's milk intake were explored.

METHODS

This study was a follow-up of children at 5.5-y of age who participated in a randomized controlled trial evaluating the effect of nutrient-enriched donor milk (commencing at ≥120 mL·kg-1·d-1) or preterm formula fed as a supplement when mother's milk was unavailable. The trial intervention lasted 90 d or until hospital discharge, whichever occurred first. In this follow-up investigation, differences in total body fat percentage determined by using air displacement plethysmography (primary outcome), fat-free mass, skinfold thickness, waist circumference, BMI z scores, and blood pressure] were evaluated using linear regressions.

RESULTS

Of 316 surviving infants from the earlier trial, 158 (50%) participated in the current study (53% male). Mean ± SD birth weight and gestational age were 1013 ± 264 g and 27.9 ± 2.5 wk. The median (IQR) intervention period was 67.5 d (52.0-91.0 d). Mean ± SD age and BMI z score at follow-up were 5.7 ± 0.2 y and -0.3 ± 1.2. Supplemental nutrient-enriched donor milk, compared to preterm formula, was not associated with growth, body composition, or blood pressure. In-hospital mother's milk intake was positively associated with height z score at 5.5 y (β: 0.07; 95% CI: 0.004, 0.1; P = 0.04).

CONCLUSIONS

Supplemental nutrient-enriched donor milk and preterm formula during initial hospitalization results in comparable long-term growth and body composition in young children born VLBW. This trial was registered at clinicaltrials.gov as NCT02759809 and at isrctn.com as ISRCTN35317141.

Feeding the Late and Moderately Preterm Infant: A Position Paper of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition Committee on Nutrition

Nutritional guidelines and requirements for late or moderately preterm (LMPT) infants are notably absent, although they represent the largest population of preterm infants. The European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) Committee on Nutrition (CoN) performed a review of the literature with the aim to provide guidance on how to feed infants born LMPT, and identify gaps in the literature and research priorities.Only limited data from controlled trials are available. Late preterm infants have unique, often unrecognized, vulnerabilities that predispose them to high rates of nutritionally related morbidity and hospital readmissions. They frequently have feeding difficulties that delay hospital discharge, and poorer rates of breastfeeding initiation and duration compared with term infants. This review also identified that moderately preterm infants frequently exhibit postnatal growth restriction.The ESPGHAN CoN strongly endorses breast milk as the preferred method of feeding LMPT infants and also emphasizes that mothers of LMPT infants should receive qualified, extended lactation support, and frequent follow-up. Individualized feeding plans should be promoted. Hospital discharge should be delayed until LMPT infants have a safe discharge plan that takes into account local situation and resources.In the LMPT population, the need for active nutritional support increases with lower gestational ages. There may be a role for enhanced nutritional support including the use of human milk fortifier, enriched formula, parenteral nutrition, and/or additional supplements, depending on factors, such as gestational age, birth weight, and significant comorbidities. Further research is needed to assess the benefits (improved nutrient intakes) versus risks (interruption of breast-feeding) of providing nutrient-enrichment to the LMPT infant.

Human milk protein vs. formula protein and their use in preterm infants

PURPOSE OF REVIEW

We review the current available evidence on the metabolic fate of human milk proteins and their potential clinical implications for growth and body composition development vs. those of formula proteins in preterm infants.

RECENT FINDINGS

The decreased content of human milk protein in preterm mothers throughout lactation might contribute to the reduced growth reported in exclusively human milk-fed infants compared with that of formula-fed infants. Recent studies have demonstrated that preterm infants are capable of degrading human milk proteins regardless of their degree of prematurity or postnatal age, with limited contribution from milk proteases to protein digestion. The nitrogen balance of fortified human milk-fed preterm infants is higher than that of formula-fed preterm infants. Moreover, the growth of human milk-fed preterm infants appears to be accompanied by fat-free mass deposition.

SUMMARY

Provided that adequate protein and energy intakes are delivered, human milk enhances protein use rather than oxidation as well as promotes tissue growth, leading to preferential fat-free mass deposition and contributing to the recovery of the body composition in preterm infants. Human milk feeding should be supported and promoted for all preterm mother-infant pairs.

The effect of maternal HIV status and treatment duration on body composition of HIV-exposed and HIV-unexposed preterm, very and extremely low-birthweight infants

BACKGROUND

There is an evidence gap regarding the relationship between HIV exposure, body composition (and the quality thereof) and preterm infants.

AIM

This study determined the body composition of HIV-exposed, preterm very low-birthweight (VLBW) and extremely low-birthweight (ELBW) infants and to assess the effect of maternal HAART duration on the body composition of this vulnerable population.

METHODS

A descriptive cross-sectional study was conducted. HIV-exposed and -unexposed preterm infants (<37 weeks) with a birthweight of ≤1200g were included. Maternal medical background was recorded. Infant body composition measurements were recorded weekly during the 28-day follow-up period.

RESULTS

Thirty preterm infants (27%) were HIV-exposed. HIV-exposed infants had significantly (=0.01) lower gestational ages than HIV-unexposed infants (25-28 weeks). HIV-exposed infants had significantly lower measurements on day 21 and day 28 for triceps skinfold (TSF) (2.5 mm vs 2.7 mm, = 0.02 and 2.6 mm vs 2.9 mm, <0.01), subscapular skinfold (SSSF) (2.3 mm vs 2.6 mm, = 0.02 and 2.4 mm vs 2.7 mm, =<0.01) and fat mass percentage (FM%) (0.9% vs 1.4%, = 0.02 and 1.0% vs 1.5%, = 0.03). HIV-exposed infants whose mothers received HAART for ≥ 20 weeks were heavier and had a higher FM% and lower fat-free mass percentage (FFM%) at birth than HIV-exposed preterm infants whose mothers received highly active antiretroviral therapy for ≥ 4- < 20 weeks.

CONCLUSION

Mothers receiving HAART could have increased risk of preterm delivery, and the duration of maternal HAART affects postnatal body composition of their infants. Body composition differs between HIV-exposed and HIV-unexposed preterm infants.

Air displacement plethysmography (pea pod) in full-term and pre-term infants: a comprehensive review of accuracy, reproducibility, and practical challenges

Air displacement plethysmography (ADP) has been widely utilised to track body composition because it is considered to be practical, reliable, and valid. Pea Pod is the infant version of ADP that accommodates infants up to the age of 6 months and has been widely utilised to assess the body composition of full-term infants, and more recently pre-term infants. The primary goal of this comprehensive review is to 1) discuss the accuracy/reproducibility of Pea Pod in both full- and pre-term infants, 2) highlight and discuss practical challenges and potential sources of measurement errors in relation to Pea Pod operating principles, and 3) make suggestions for future research direction to overcome the identified limitations.

Can Basic Characteristics Estimate Body Composition in Early Infancy?

OBJECTIVES

Increasing evidence demonstrates that body composition in early life contributes to the programming of health later in life in both full-term and preterm infants. Given the important role of body composition, the increased availability of easy, noninvasive, and accurate techniques for its assessment has been recommended. The aim of the present study was to identify basic characteristics and anthropometric measurements that best correlate with body composition in infants.

METHODS

Anthropometric measurements and body composition assessed by air-displacement plethysmography were assessed either at birth or at term-corrected age in 1239 infants (654 full-term, 585 preterm). The associations of sex, GA (gestational age), and weight with FFM (fat-free mass) and FM (fat mass) adjusted by length (g/cm) were investigated by multiple linear regression models. Bland-Altman tests were performed, and an equation for calculating FFM was determined.

RESULTS

Preterm infants exhibited increased FM and reduced FFM compared with full-term infants (477.6 ± 204 vs 259.7 ± 147 g and 2583 ± 494 vs 2770 ± 364 g, respectively). GA, male sex, and weight were positively associated with FFM (r = 0.806, P < 0.0001; 6.1 g of average bias). GA and male sex were negatively associated with FM, whereas weight was positively associated with FM (r = 0.641, P < 0.0001; 4.9 g of average bias).

CONCLUSIONS

The assessment of body composition represents the criterion standard. When body composition assessment is not feasible, the equation based on sex, GA, and anthropometric measurements can be useful in predicting body composition in both full-term and preterm infants.

Protein use and weight-gain quality in very-low-birth-weight preterm infants fed human milk or formula

Background

Nutritional management of preterm infants aims to approximate the tissue growth and body composition of a fetus of the same postmenstrual age. The adequacy of the quality of protein supply can influence the rate and the relative quality of weight gain.

Objective

We investigated the protein balance according to feeding regimen and the association between human milk feeding and fat-free mass content at the term-corrected age in very-low-birth-weight preterm infants.

Design

A prospective observational study was conducted. Inclusion criteria were as follows: healthy infants, gestational age ≤32 wk, birth weight <1500 g, stable clinical conditions, and feeding by mouth with human milk or formula at discharge. Infants were enrolled at hospital discharge. At enrollment, macronutrient intakes and protein balance were determined. Anthropometric measurements and body composition were also assessed. The nutritional composition of human milk was calculated by infrared spectroscopy. The protein balance was determined according to the nitrogen balance standard method. Body composition was assessed by an air-displacement plethysmography system. At the term-corrected age, anthropometry and body composition assessments were repeated.

Results

Seventeen preterm infants fed fortified human milk and 15 preterm infants fed formula were enrolled. At discharge, despite similar macronutrient intakes, infants fed fortified human milk showed a higher nitrogen balance (expressed as mg · kg-1 · d-1) compared with preterm formula-fed infants (mean ± SD: 488.3 ± 75 compared with 409.8 ± 85 mg · kg-1 · d-1, P = 0.009). At term-corrected age, growth was similar in the 2 groups, whereas fortified human milk-fed infants showed a higher percentage of fat-free mass (85.1% ± 2.8% compared with 80.8% ± 3.2%, P = 0.002). Moreover, at multiple linear regression, fat-free mass content was independently associated with being fed human milk (R2 = 0.93, P < 0.0001).

Conclusion

Our findings suggest that human milk feeding is associated with early fat-free mass deposition in healthy and stable preterm infants. This trial was registered at www.clinicaltrials.gov as NCT03013374.

The Effect of Human Milk on Modulating the Quality of Growth in Preterm Infants

Introduction: Human milk is the optimal nutrition for preterm infants. When the mother's own milk is unavailable, donor human milk is recommended as an alternative for preterm infants. The association among early nutrition, body composition and the future risk of disease has recently attracted much interest. The aim of this study was to investigate the effect of human milk on the body composition of preterm infants. Materials and Methods: Very low birth weight infants (VLBW: birth weight <1,500 g) with a gestational age (GA) between 26 and 34 weeks were included. Clinical data, anthropometric measurements and nutritional intake in terms of the volume of human milk were extracted from computerized medical charts. The human milk intake was expressed as a percentage of target fortified donor human milk and/or target fortified fresh mother's milk, compared with the total volume of milk intake during the hospital stay. All included infants underwent anthropometric measurements and body composition analysis (expressed as fat-free mass percentage) at term corrected age (CA) by air-displacement plethysmography. A comparison between infants fed human milk at <50% (group 1) and infants fed human milk at ≥50% of the total volume of milk intake (group 2) was conducted. Multiple linear regression analyses were conducted to explore the modulating effect of fortified human milk on fat-free mass at term CA. Results: Seventy-three VLBW infants were included in the study. The mean weight and GA at birth were 1,248 ± 198 g and 30.2 ± 2.0 weeks, respectively. No differences were found regarding anthropometric measurements at birth, at discharge and at term CA between the two groups. The mean fortified human milk intake was 34.9 ± 12.5 and 80.9 ± 15.5% in groups 1 and 2, respectively (p < 0.001). A multiple regression analysis corrected for sex and birth weight demonstrated that intake of ≥50% fortified human milk was associated with a higher fat-free mass percentage at term CA than intake of <50% fortified human milk. Conclusion: The use of target fortified human milk modulated growth and improved growth quality in vulnerable preterm infants. Thus, the use of donor human milk should be encouraged when fresh mother's milk is insufficient or not available.