As to be expected, the long term health of preterm infants is influenced by nutritional support. To ensure they receive optimal nutrition, preterm infants require close monitoring during their hospital stay and post discharge. This is especially important for babies with poor growth, as identified by their head circumference and weight and length measurements¹.

Preterm babies often suffer further complications which may exacerbate their nutritional situation. Their need for special care does not end on discharge.

Responsible for more than clinical management, the Healthcare Professional (HCP) provides support and information to the parents in the early months. In an interview with Registered Nutritionist Michelle Chida, we explore the different feeding options available for preterm infants following their discharge from hospital.

Q. What choice of feeds is available for preterm infants?

Breastmilk is the preferred feeding choice for all infants - including preterm infants – as part of their hospital and discharge care. In hospital and on discharge, breastfeeding is ideally on demand, and feeding regimes are adjusted according to careful monitoring of the infant’s biochemistry and weight gain. If the nutrient density of breastmilk is inadequate, it may need fortification or supplementation.

Q. What happens when the preterm infant is discharged?

In hospital, some neonatal units have a discharge care team which includes Neonatologists, Dietitians, Infant Feeding Advisors and Neonatal Nurses. Together they provide the family with careful advice as well as a discharge plan including feeding advice.

Following the infant’s discharge, other Healthcare Professionals including General Practitioners (GP), Practice Nurses and Health Visitors are also involved with providing continuing care and support.

It is therefore important that HCPs caring for preterm infants are aware of the latest guidelines on nutrition for the discharged preterm infant. They need to know all the options available in order to help them manage and adapt the care specific to the infant, and support the parents.

Most preterm infants exhibit some degree of catch up growth during their first few months¹. The rates of growth vary and are dependent on many factors, such as birth weight, gestational age, appropriate intrauterine growth, neurological status, clinical course or other co-morbidities of prematurity, and nutrition^2.

Q. Does the breastfed preterm infant ‘do’ better?

If an infant has appropriate weight for postconceptual age, he or she should be breastfed if possible. Breastfed preterm infants demonstrate significant growth and neurodevelopmental advantages compared to formula fed infants^3,4. There is also a positive relationship between the duration of breastfeeding and the later Bayley MentalIndex that measures an infant’s cognitive, motor, and behavioural development. Furthermore, breastfeeding is linked to a reduction in the number of serious adverse events i.e. the number of hospitalisation episodes after discharge¹. The duration of breastfeeding also has a significant advantage to bone mass in later life⁵.

Q. Can fortification or supplementation of breastmilk help?

Breastfed infants may not be able to consume enough milk to meet their increased protein, calcium and phosphorus requirements. Extremely low birthweight infants who are fed breastmilk fortified or supplemented with other nutrients have been shown to have improved length and head circumference gains after discharge.



It can be a dilemma for some Healthcare Professionals to ensure that the infant’s nutritional needs for growth are met whilst at the same time, encourage exclusive breastfeeding. Additional nutrition supplementation of breastmilk may be required for infants who cannot sustain optimal growth or achieve ad lib milk intake, or for infants with sub optimal biochemical measurements that indicate nutrition risk.

The supplementation should be in the form of a breastmilk fortifier such as Cow & Gate Nutriprem Breastmilk Fortifier or an infant formula (like Cow & Gate Nutriprem 1) that meets the overall nutritional needs of the infant; it should be fed from a cup or bottle. Breastmilk fortifier is not available on prescription, though some units will supply some for use on discharge.

Supplementation can continue until the infant’s growth and biochemical measurements of nutritional status are within the normal range or clinically acceptable.

Exclusively breastfed infants require an iron supplement at 2mg per kilogram body weight per day and a multivitamin supplement. If the infant is fed both breast and formula milk this quantity may need to be adjusted ⁵.

Click here for practical advice and insight on a typical discharge plan.

Q. What about preterm infants that are not breastfed after
discharge?
While no formula can ever be a perfect substitute for mother’s own milk, there are alternative feeding options for preterm infants. These substitutes are continually researched and developed to improve their nutritional value. They are proven to be safe and effective, but are still a second choice to breastmilk⁷. In addition, some formulas such as Cow & Gate Nutriprem 2 include prebiotic oligosaccharides.

Q. What are the benefits of preterm post discharge formula?

Cow & Gate Nutriprem 2, has an energy density and nutrient content that is intermediate to the infant from preterm formulas used in hospitals and the standard formulas for term infants. These are designed to deliver appropriate nutrition in a smaller volume over a period of rapid growth.

Another advantage of using a preterm post discharge formula is a reduction in the need for separate iron and/or vitamin supplements. When parents administer such supplements to the infant it exposes the risk of inaccurate doses being given.

Feeding a post discharge formula rather than a term formula may also allow an infant with nutritional deficits to accumulate stores and facilitate catch up growth. This is because the infant consumes more nutrients in smaller volumes of the nutrient rich and energy dense feed.

ESPGHAN guidelines recommend a nutrient enriched post-discharge formula until at least 40 weeks and probably 52 weeks post conception age¹.

Click here for practical advice and insight on the main categories of growth.


Q. Should preterm infants be fed with a term infant formula?

Standard infant formulas are designed to meet nutritional needs of the term infant. Preterm infants have greater nutritional needs than term infants. Preterm infants who are fed a standard term infant formula before hospital discharge grow more slowly. They typically have reduced weight and head circumference, compared to those fed a specially formulated preterm infant formula. During the last trimester there is rapid brain growth and accumulation of nutrient stores. During this time an inadequate intake may also limit brain growth and, therefore, development ⁸.

Several studies show the benefits of enriched post discharge formula on neurodevelopment, bone accretion and general growth. Many long term post discharge feeding studies typically report that infants who are fed standard term formula consume higher volumes.

Q. What about catch-up growth?

The neonatal period is critical for metabolic programming and poor nutritional management could have serious consequences in later life. Preterm babies grow slower in the first few months than term babies. Some infants are at risk of malnutrition when they are discharged from hospital, and preterm infants may have a significant nutritional deficit that needs to be addressed after discharge².

The aim of nutrient enriched formula or fortification of expressed breastmilk is to achieve early catch up growth, and to reduce deficits that the preterm infant has missed out on during the last trimester of gestation - a time when nutrient accumulation occurs.

The additional nutrients may be required to compensate for the nutrient deficits that are present as a result of the infant being born early as well as those accumulated in the early post natal period. Each preterm infant has to be treated individually, they are different to term infants and may also have complications of prematurity. The window in which preterm infants can catch up with growth is narrow. There is a critical period - approximately one year - for optimal growth for head circumference, and up to three years for height⁹,¹⁰.

The optimal growth and nutrition in preterm babies is a subject of ongoing debate. Historically, the approach is typically provision of high energy and nutrients to promote early catch up growth in preterm and very low birthweight infants.

There is conflicting information in the literature. A Cochrane review¹¹ found significant difference in length (crown – heel) at 18 months age post term, without significant difference in neurodevelopment when using a post-discharge formula. This review contained trials of varying study design so data synthesis was limited.

The role of specific substrates in the formulas has however been documented. For example, long chain polyunsaturated fatty acids supply may benefit visual acuity in very low birthweight infants; and zinc has a role in growth and motor development¹¹.



Q. When and how should weaning of the preterm infant commence?

The Department of Health (DH) recommends that for preterm infants, weaning may be advised if the infant weighs at least 5kg, is able to eat from a spoon and has lost the extrusion reflux (when the infant pushes material out from the anterior part of the mouth, perhaps as a protective mechanism). Infants who are born preterm should not be fed solids before four months chronological age (17 weeks post delivery), unless there are special circumstances with support of the Healthcare Professional.

Delaying weaning until four months post term may mean that the infant is consuming breastmilk or formula milk for a long time and this could compromise their nutritional status⁴ and development. Certainly weaning should have commenced by seven months chronological age (post delivery). The timing of weaning for preterm infants is important for their development. If solids are not introduced before seven months there is a risk of feeding problems.

Healthcare Professionals should encourage and support parents to follow DH recommendations. They need to consider a number of factors including the type of milk feeding and the current weight and weight gain of the infant in conjunction with age when advising parents on weaning.

Q. What is the outlook for preterm infants, post discharge?

The outlook for preterm babies, post discharge, is improving all the time, especially as nutritional options are better understood and applied. With so many more preterm babies now being discharged home, more community HCPs are becoming actively involved in their care. It is no longer unusual for HCPs to work with such families.

As a result, HCPs are continually developing their knowledge, skill and insight, especially when it comes to giving practical advice and support regarding optimising the nutrition of preterm infants, post discharge. This is a critical time for babies’ growth and development, one that is proven to impact long term health. Ongoing research will continue to clarify the optimal post discharge nutrition for preterm infants.

Click here for practical advice and insight on preterm infants that are appropriate or underweight for post conceptual age.

Click here for more information on the Cow & Gate Nutriprem range or to download a copy of our Specialist Infant Milks leaflet If parents would like information on feeding thier preterm baby why not tell them to visit the Cow & Gate website hereClick here to view the latest research on preterm infant milk formulas


References
1. ESPGHAN Medical Position Paper. JPGN May 2006;42:596-603.
2. Carver JD. Adv Pediatr. 2005;52:23-47
3. Lucas A, et al. Pediatrics 2001;108:703
4. Morley R, et al. Pediatrics 2004;113:515
5. Schanler R. Acta Paediatr. 2005;94 (suppl 449): 68-73.
6. Norris FJ et al. EJCN 2002;56:448-454
7. Manual of Dietetic Practice. Fourth Edition. Eds Thomas & Bishop. Section 3.2 Nutritional needs of preterm infants. Blackwell Publishing. ISBN 978-1-4051-3525-2.
8. Cooke RJ et al. Paediatric Research Volume March 1998; 43(3):355-360
9. Gale C R et al, Critical periods of brain growth and cognitive function in children. Brain 2004 127: 321-9
10. Harding J E, McCavan C M, Perinatal prediction of growth patters to 18 months in babies born small for gestational age. Early Human Development 2003 74: 13-26
11. Henderson G, et al. Cochrane Database Syst Rev. 2007 Oct 17;(4):CD004862. M Chida accessed Nov 2008.