Preterm infants are just like any other babies – some learn more quickly than others and parents will often need reassurance. It can take weeks before a sucking reflex is established well enough for baby to feed properly as this also depends on their general condition and how prematurely they were born.
If a baby being tube fed starts opening and closing their mouth during the feed, they are probably ready to practice sucking. Giving them a dummy (pacifier) can often help develop the reflex. It has been shown that this can help the preterm baby make the move from tube-feeding to normal feeding1.
Sometimes called ‘non-nutritive suckling’, this has also been shown to help with gastric motor functions2 and craniofacial/dental development3.
As soon as possible after birth, mothers should be encouraged to express breast milk as often as they can. This can then be frozen and stored for when the baby is ready to take it.
But for those mothers in hospital who are not able to provide breast milk, a specially designed low birth weight infant formula is available. This contains the particular nutrients in proportions that the preterm baby needs and will usually be given by naso-gastric or oro-gastric tube until baby can manage the sucking/swallowing/breathing process when they can begin to be bottle-fed.
Even by the time they leave hospital, low birth weight/preterm infants weigh less4,5 and have lower nutrient stores than term babies6. Specially developed ‘Premature formulas’ have been created to provide the extra protein, energy, vitamins and minerals needed by preterm infants.
How long an infant will need to stay on a Premature formula will depend on their individual weight and progress. The smaller the premature baby is at birth, the more benefit is likely to be derived from an enriched premature formula. There are no established guidelines for when a premature formula should be used or for when the transition to a ‘term’ formula should be made but clinical studies have demonstrated benefits of premature formulas for up to12 months.
Their use is recommended by ESPGHAN (The European Society of Paediatric Gastroenterology, Hepatology and Nutrition) until a post-conceptual age of 40-52 weeks7. The observation of the Committee on Nutrition, American Academy of Pediatrics 2009 is that premature formulas are often continued until 9-12 months corrected age or till the baby’s weight for age is maintained above the 25th percentile8.
Preterm infants have nutrient deficiencies due to their premature birth and can benefit from earlier weaning than term infants. Term babies usually begin weaning around four to six months but preterm infants can start weaning 5-7 months from birth9,10.
The signs that a preterm baby is ready to start weaning are the same as those for a term baby – putting things in their mouth, showing interest in other people eating and seeming to want more than just milk.
Babies start using their mouths to explore toys at about 4 months but may not have a sufficiently developed digestive system to take solid food before 5 months. Reducing the proportion of milk to solid foods too early may affect the right intake of nutrients and affect growth. It is important not to start weaning too early but equally important not to wait too long11 – starting solids and chewing helps mouth and jaw development.
Although weaning often begins when the infant is comfortable being supported in a sitting position, it is important to support head and back when feeding to reduce the risk of choking.
1. Field T, et al. Non-nutritive suckling during tube-feeding: effects on preterm neonates in an intensive care unit. Pediatrics 1982; 70: 381-384.
2. Widstrom A, et al. Non-nutritive suckling in tube-fed preterm infants: effects on gastric motility and gastric contents of somatostatin. JPGN 1088; 7: 517-523.
3. Radzi Z and Yahya N. Relationship between breastfeeding and bottle feeding to craniofacial and dental development. Annal Dent Uni Malay 2005; 12: 9-17.
4. Carlson S. Feeding after discharge: growth, development and long-term effects. In Tsang R et al. Nutrition of the preterm infant: Scientific basis and practical guidelines. 2nd Ed. Cincinnati, OH: Dgital Education Publishing, Inc: 2005: 357-381.
5. Casey PH. Growth of low birth weight preterm children. Semin Perinatol 2008; 32: 20-27.
6. Henderson G, et al. Nutrient-enriched formula versus standard term formula for preterm infants following hospital discharge. Cochrane Database Syst Rev 2007; 4:CD004696.
7. Aggett PJ, et al. Feeding preterm infants after hospital discharge – A commentary by the ESPGHAN committee on nutrition. JPGN 2006; 42: 596-603.
8. AAP Committee on Nutrition, Kleinman R. Pediatric Nutrition Handbook, 6th Edition. American Academy of Pediatrics, 2009.
9. King C. Preterm infants. In: Shaw V, et al. Clinical Paediatric Dietetics, Eds. Blackwell Publishing 2007; 6: 73-89.
10. King C, et al. Weaning your premature baby, 3rd edition. London: BLISS 2006.
11. Foote KD and Marriott LD. Weaning of infants. Arch Dis Child 2003; 88: 488-492.