The birth of a child is a joyous occasion, but when a baby arrives prematurely, it can bring unique challenges. Preterm infants, those born before 37 weeks of gestation, require specialized care, particularly in terms of nutrition. The nutritional needs of preterm infants are significantly different from those born at term, as their organs and systems are not fully developed. Early and exclusive nutrition with human milk plays a crucial role in supporting their growth and development, laying the foundation for their future health and well-being.

Understanding Preterm Birth

Preterm birth is a global health issue, affecting millions of infants each year. According to the World Health Organization (WHO), an estimated 13.4 million babies are born preterm annually, accounting for approximately 1 in 10 births worldwide. India had the highest number of preterm births in 2020 (3.02 million, accounting for over 23% of all preterm births worldwide). Preterm birth continues to be the leading cause of under-5 child mortality, accounting for around 1 million newborn deaths globally in 2021, a figure comparable to ten years ago. The causes of preterm birth are complex and multifactorial, encompassing factors such as maternal health, socioeconomic status, access to healthcare, and environmental influences.

Nutritional Challenges Faced by Preterm Infants

Preterm birth disrupts the natural process of fetal development, depriving the infant of vital nutrients and growth factors normally acquired during the final weeks of gestation. As a result, preterm infants are at increased risk of nutritional deficiencies and growth faltering. The challenges faced by preterm infants include:

1. Immature Organ Function: Preterm delivery problems are caused by immature organ systems that are not yet ready to maintain life outside of the uterus. The risk of acute newborn disease decreases with gestational age, indicating the immaturity of the brain, lungs, immune system, kidneys, skin, eyes, and digestive system. In general, more immature preterm newborns require additional life support. The susceptible complications include necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), and sepsis.^,

2. Increased Nutrient Requirements: Preterm infants have higher nutrient requirements compared to full-term infants to support their rapid growth and development. They require additional protein, calories, vitamins, and minerals to meet their nutritional needs and promote optimal growth.

3. Limited Nutrient Stores: Preterm infants are born with limited nutrient stores, particularly fat and glycogen, which are essential for energy metabolism and thermoregulation. As a result, they may be more prone to hypoglycemia and hypothermia in the early postnatal period.

4. Feeding Intolerance: Preterm infants may experience feeding intolerance, characterized by difficulty tolerating enteral feeds and increased risk of gastrointestinal complications such as reflux, vomiting, and abdominal distension. These challenges can hinder the delivery of essential nutrients and contribute to poor growth outcomes.

Importance of Early and Exclusive Human Milk Diet

Early and exclusive nutrition with human milk is critical for preterm infants to promote growth, development, and overall health. Providing adequate nutrition from the earliest stages of life can help mitigate the adverse effects of preterm birth and optimize long-term outcomes. Enteral nutrition is the preferred route of nutrition for its benefits compared to parenteral nutrition in the long term.  Human breastmilk is the preferred source of nutrition for preterm infants due to its unique composition and numerous health benefits. Breast milk provides essential nutrients, growth factors, immune factors, and bioactive components that support optimal growth and development. It also offers protection against infections, reduces the risk of NEC and other complications, and promotes neurodevelopmental outcomes. The following are key components of early, enteral, and exclusive human milk diet for preterm infants:

• Early Enteral Feeding: 

Preterm newborns’ nutritional requirements are best satisfied by enteral feeding. Though parenteral nutrition remains an option for providing vital nutrition following preterm birth, the data shows that enteral feeding continues to give important nutritional and non-nutritional advantages. The evidence supports the early commencement and progression of enteral feeding on preterm baby health by boosting micronutrient delivery, promoting intestinal development and maturation, stimulating microbiota formation, lowering inflammation, and enhancing brain growth and neurodevelopment.

• Mother’s Own Milk (MOM):

Whenever possible, efforts should be made to establish and maintain breastfeeding with the mother’s own milk (MOM) for preterm infants. MOM is specifically tailored to meet the nutritional needs of the infant and provides immunological protection against infections. Mothers of preterm infants may require support and assistance to initiate and sustain breastfeeding, including guidance from lactation consultants, access to breast pumps, and accommodations for skin-to-skin contact and kangaroo care.

• Pasteurized Donor Human Milk (PDHM):

In cases where MOM is unavailable or insufficient, pasteurized donor human milk (PDHM) which is the next preferred nutritional option can serve as a valuable alternative for preterm infants. DHM is pasteurized to ensure safety while preserving most of its nutritional and immunological properties. It offers most of the benefits of MOM, including protection against infections and the promotion of healthy growth and development. But MOM is superior to PDHM. Access to donor milk banks and screening processes for donor selection are essential to ensure the quality and safety of PDHM.^,

• Fortified Human Milk:

To meet the increased nutrient requirements of preterm infants, human milk mother-expressed breast milk or PDHM needs to be fortified with human milk fortifiers. Fortification of human milk with human milk-based fortifiers constitutes an exclusive human milk diet (EHMD) which substantiates providing natural human nutrients to preterm infants. Fortification helps enhance the caloric and nutrient content of breast milk, ensuring that preterm infants receive adequate protein, fat, carbohydrates, vitamins, and minerals for growth and development. Individualized fortification protocols may be tailored based on the infant’s gestational age, weight, and nutritional status.^,

• Nutritional Support:

In addition to human milk feeding, preterm infants may require nutritional supplementation to meet their specific needs. Nutritional support may include protein supplements, medium-chain triglycerides (MCT) oil, omega-3 fatty acids, and micronutrient supplements such as iron, calcium, and vitamin D. Close monitoring of growth parameters, nutritional intake, and biochemical markers is essential to assess nutritional status and adjust feeding regimens accordingly.

Conclusion

The nutritional needs of preterm infants are unique and require specialized care to support their growth and development. Early and exclusive enteral nutrition, particularly through human milk feeding, plays a crucial role in promoting optimal outcomes for preterm infants. By providing adequate nutrition from the earliest stages of life, healthcare providers can help mitigate the challenges associated with preterm birth and set the foundation for long-term health and well-being. Through a multidisciplinary approach that involves collaboration between healthcare professionals, lactation support specialists, and families, we can ensure that preterm infants receive the nutrition they need to thrive.

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