Banked preterm versus banked term human milk to promote growth and development in very low birth weight infants

Review question
When mother's own milk is not available or is insufficient, does feeding banked donor preterm milk compared to banked donor term milk result in improved growth and neurodevelopmental outcome in very low birthweight infants?

Background
Donor-expressed milk processed by human milk banks has been used to provide preterm infants with breast milk when there are circumstances that preclude the use of mother's own milk. Preterm milk differs significantly from term breast milk. The processes involved in providing donor milk, including freezing, thawing and pasteurisation has adverse effects on nutritional and non-nutritional aspects of donor milk. Donor milk is expensive. We wished to determine whether the benefits of preterm donor milk were superior to term donor milk either as a sole diet, or as a supplement to mother's own milk.

Study characteristics
We were unable to identify any studies that compared donor preterm milk with donor term milk to promote growth and development in very low birth weight infants. Evidence is up to date as of October 2018.

Key results
We were unable to conclude that donor preterm milk was superior to term donor milk as there is no evidence to support or refute this question. However the lack of studies identified in the original review and now updated in this review means that it is extremely unlikely that any such study will be performed.

Quality of evidence
There were no studies to make an assessment of quality of evidence.

Authors' conclusions: 

We found no evidence to support or refute the effect of banked donor preterm milk compared to banked term milk regarding growth and developmental outcomes in very low birth weight infants.

Read the full abstract...
Background: 

Human milk banking has been available in many countries for the last three decades. The milk provided from milk banking is predominantly term breast milk, but some milk banks provide preterm breast milk. There are a number of differences between donor term and donor preterm human milk.

Objectives: 

To determine the effect of banked donor preterm milk compared with banked donor term milk regarding growth and developmental outcomes in very low birth weight infants (infants weighing less than 1500 grams).

Search strategy: 

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 7), MEDLINE via PubMed (1966 to 23 October 2018), Embase (1980 to 23 October 2018), and CINAHL (1982 to 23 October 2018). We also searched clinical trial databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

Selection criteria: 

Randomised and quasi-randomised trials comparing banked donor preterm milk with banked donor term milk regarding growth and developmental outcomes in very low birth weight infants

Data collection and analysis: 

We planned to perform assessment of methodology regarding blinding of randomisation, intervention and outcome measurements as well as completeness of follow-up. We planned to evaluate treatment effect using a fixed-effect model using relative risk (RR), relative risk reduction, risk difference (RD) and number needed to treat for an additional beneficial outcome (NNTB) or the number needed to treat for an additional harmful outcome (NNTH) for categorical data; and using mean, standard deviation and weighted mean difference (WMD) for continuous data. We planned to use the GRADE approach to assess the quality of evidence.

Main results: 

No studies met the inclusion criteria.