Importance: Breastfed infants are at risk of iron deficiency, which is associated with suboptimal development. There is a paucity of evidence on the effects of iron supplementation on child development, and current guidelines are divergent.Objective: To assess whether daily iron supplementation, 1 mg/kg, between 4 and 9 months in exclusively or predominantly breastfed infants improves psychomotor development at 12 months.Design, Setting, and Participants: This was a randomized, double-blind, placebo-controlled trial conducted between December 2015 and May 2020 with follow-up through May 2023 in an outpatient setting in Poland and Sweden. Participants were healthy singleton infants born at term with birth weight greater than 2500 g who were exclusively or predominantly breastfed (>50%) and did not have anemia (hemoglobin >10.5 g/dL) at age 4 months. Exclusion criteria included major illness, congenital anomaly, food allergy, and difficulty communicating with caregivers.Interventions: Iron (micronized microencapsulated ferric pyrophosphate), 1 mg/kg, or placebo (maltodextrin) once daily from age 4 to 9 months.Main Outcomes and Measures: The primary outcome was psychomotor development assessed by motor score of Bayley Scales of Infant and Toddler Development III at 12 months, adjusted for gestational age, sex, and maternal education. Secondary outcomes included cognitive and language scores at 12 months; motor, cognitive, and language scores at 24 and 36 months; iron deficiency (serum ferritin <12 ng/mL), and iron deficiency anemia (iron deficiency and hemoglobin <10.5 g/dL) at 12 months.Results: Of 221 randomized infants (111 female), 200 (90%) were included in the intention-to-treat analysis (mean [SD] age, 12.4 [0.8] months). Iron supplementation (n = 104) compared to placebo (n = 96) had no effect on psychomotor development (mean difference [MD] for motor score, −1.07 points; 95% CI, −4.69 to 2.55), cognitive score (MD, −1.14; 95% CI, −4.26 to 1.99), or language score (MD, 0.75; 95% CI, −2.31 to 3.82) at 12 months. There were no significant differences at 24 and 36 months. The intervention did not reduce the risk for iron deficiency (relative risk [RR], 0.46; 95% CI, 0.16 to 1.30) or iron deficiency anemia (RR, 0.78; 95% CI, 0.05 to 12.46) at 12 months.Conclusion and Relevance: No benefit was found with daily low-dose iron supplementation between 4 and 9 months with respect to psychomotor development, risk of iron deficiency, or iron deficiency anemia among breastfed infants in a setting of low risk of anemia.Trial Registration: ClinicalTrials.gov Identifier: NCT02242188

Background: At term-equivalent age, infants born prematurely are shorter, lighter and have more adipose tissue compared to term counterparts. Little is known on whether the differences in body composition persist in later age. Methods: We prospectively recruited 33 preterm infants (<32 weeks gestational age, mean gestational age 28.1 weeks) and 69 term controls. Anthropometry and body composition (air displacement plethysmography) were monitored up to 4 months of age. Nutrient intakes from preterm infants were collected from clinical records. Results: At 4 months of age preterm infants were lighter and shorter than term controls (mean weight-for-age z-score: –0.73 vs. 0.06, p = 0.001; mean length-for-age z-score: –1.31 vs. 0.29, p < 0.0001). The significantly greater percentage of total body fat seen in preterm infants at term-equivalent age (20.2 vs. 11.7%, p < 0.0001) was no longer observed at 4 months. A deficit of fat-free mass persisted until 4 months of age (fat-free mass at term-equivalent age: 2.71 vs. 3.18 kg, p < 0.0001; at 4 months: 4.3 vs. 4.78 kg, p < 0.0001). The fat mass index and fat-free mass index (taking length into account) did not differ between the groups. Nutrition had little effect on body composition. Higher protein intake at week 2 was a negative predictor of fat-free mass at discharge. Conclusions: At 4 months corrected age, preterm infants were both lighter and shorter than term controls and the absolute fat-free mass deficit remained until this age. Little effect of nutrition on body composition was observed.

Human milk is recommended for very low birth weight infants. Their nutritional needs are high, and the fortification of human milk is a standard procedure to optimize growth. Targeted fortification accounts for the variability in human milk composition. It has been a promising alternative to standard fixed-dose fortification, potentially improving short-term growth. In this trial, preterm infants (≤32 weeks of gestation) were randomized to receive human milk after standard fortification (HMF, Nutricia) or tailored fortification with modular components of proteins (Bebilon Bialko, Nutricia), carbohydrates (Polycal, Nutricia), and lipids (Calogen, Nutricia). The intervention started when preterms reached 80 mL/kg/day enteral feeds. Of the target number of 220 newborns, 39 were randomized. The trial was interrupted due to serious intolerance in five cases. There was no significant difference in velocity of weight gain during the supplementation period (primary outcome) in the tailored vs. standard fortification group: 27.01 ± 10.19 g/d vs. 25.84 ± 13.45 g/d, p = 0.0776. Length and head circumference were not significantly different between the groups. We found the feasibility of targeted fortification to be limited in neonatal intensive care unit practice. The trial was registered at clinicaltrials.gov NCT:03775785.

Human milk is recommended for all very low birth weight infants. Breastmilk is highly variable in nutrient content, failing to meet the nutritional demands of this group. Fortification of human milk is recommended to prevent extrauterine growth retardation and associated poor neurodevelopmental outcome. However, standard fortification with fixed dose multicomponent fortifier does not account for the variability in milk composition. Targeted fortification is a promising alternative and needs further investigation. This randomized controlled trial will recruit preterm infants (≤ 32 weeks of gestation) within the first 7 days of life. After reaching 80 ml/kg/day of enteral feeding, patients will be randomized to receive standard fortification (HMF, Nutricia) or targeted fortification (modular components: Bebilon Bialka, Nutricia—protein; Polycal, Nutricia—carbohydrates; Calogen, Nutricia—lipids). The intervention will continue until 37 weeks of post-conception age or hospital discharge. Parents and outcome assessors will be blinded to the intervention. The primary outcome measure is velocity of weight, length, and head growth until 36 weeks post-conceptional age or discharge. Secondary outcomes include neurodevelopment at 12 months assessed with Bayley Scale of Development III, repeated at 36 months; body composition at discharge and at 4 months; and incidence of necrotizing enterocolitis, sepsis, retinopathy of prematurity, and bronchopulmonary dysplasia. Targeted fortification has previously been shown as doable in the neonatal intensive care unit context. If it shows to improve growth and neonatal outcome, choosing the targeted fortification as a first line nutritional approach in very low birth weight infants may become a recommendation. ClinicalTrials.gov NCT03775785, Registered on July 2019.