(1) Introduction: Current evidence on managing infants under six months with growth failure or other nutrition-related risk is sparse and low quality. This review aims to inform research priorities to fill this evidence gap, focusing on breastfeeding practices. (2) Methods: We searched PubMed, CINAHL Plus, and Cochrane Library for studies on feeding interventions that aim to restore or improve the volume or quality of breastmilk and breastfeeding when breastfeeding practices are sub-optimal or prematurely stopped. We included studies from both low- and middle-income countries and high-income countries. (3) Results: Forty-seven studies met the inclusion criteria. Most were from high-income countries (n = 35, 74.5%) and included infants who were at risk of growth failure at birth (preterm infants/small for gestational age) and newborns with early growth faltering. Interventions included formula fortification or supplementation (n = 31, 66%), enteral feeds (n = 8, 17%), cup feeding (n = 2, 4.2%), and other (n = 6, 12.8%). Outcomes included anthropometric change (n = 40, 85.1%), reported feeding practices (n = 16, 34%), morbidity (n = 11, 23.4%), and mortality (n = 5, 10.6%). Of 31 studies that assessed formula fortification or supplementation, 30 reported anthropometric changes (n = 17 no effect, n = 9 positive, n = 4 mixed), seven morbidity (n = 3 no effect, n = 2 positive, n = 2 negative), five feeding (n = 2 positive, n = 2 no effect, n = 1 negative), and four mortality (n = 3 no effect, n = 1 negative). Of eight studies that assessed enteral feed interventions, seven reported anthropometric changes (n = 4 positive, n = 3 no effect), five feeding practices (n = 2 positive, n = 2 no effect, n = 1 negative), four morbidity (n = 4 no effect), and one reported mortality (n = 1 no effect). Overall, interventions with positive effects on feeding practices were cup feeding compared to bottle-feeding among preterm; nasogastric tube feed compared to bottle-feeding among low birth weight preterm; and early progressive feeding compared to delayed feeding among extremely low birth weight preterm. Bovine/cow milk feeding and high volume feeding interventions had an unfavourable effect, while electric breast pump and Galactagogue had a mixed effect. Regarding anthropometric outcomes, overall, macronutrient fortified formula, cream supplementation, and fortified human milk formula had a positive effect (weight gain) on preterm infants. Interventions comparing human breastmilk/donor milk with formula had mixed effects. Overall, only human milk compared to formula intervention had a positive effect on morbidity among preterm infants, while none of the interventions had any positive effect on mortality. Bovine/cow milk supplementation had unfavourable effects on both morbidity and mortality. (4) Conclusion: Future research should prioritise low- and middle-income countries, include infants presenting with growth failure in the post-neonatal period and record effects on morbidity and mortality outcomes.
Keywords: breastfeeding; growth failure; infant; malnutrition.