Does feeding preterm or low birth weight infants with formula rather than maternal breast milk affect growth and development?
Artificial formulas can be manipulated to contain higher amounts of important nutrients such as protein than maternal breast milk but newborn infants often find formula difficult to digest. Artificial formulas, furthermore, do not contain the antibodies and other substances present in breast milk that protect the immature gut of preterm or low birth weight infants and reduce the risk of infection and severe bowel problems. If preterm infants are fed with formula rather than maternal breast milk (breast-fed directly or mother's own expressed breast milk), this might increase the risk of these problems and adversely affect growth and development. Given these concerns, we planned to review the evidence from clinical trials that compared formula versus maternal breast milk for feeding preterm or low birth weight infants.
In searches up to October 2018, we did not find any eligible randomised controlled trials.
Key results and conclusions
There are no trial data to answer this question. Since another Cochrane Review showed that feeding with formula compared to donor breast milk increases the risk of serious gut problems in preterm or low birth weight infants, it is unlikely that families and clinicians would consider it acceptable to allocate an infant to receive formula as an alternative to maternal breast milk when it is available.
There are no trials of formula versus maternal breast milk for feeding preterm or low birth weight infants. Such trials are unlikely to be conducted because of the difficulty of allocating an alternative form of nutrition to an infant whose mother wishes to feed with her own breast milk. Maternal breast milk remains the default choice of enteral nutrition because observational studies, and meta-analyses of trials comparing feeding with formula versus donor breast milk, suggest that feeding with breast milk has major immuno-nutritional advantages for preterm or low birth weight infants.
Artificial formula can be manipulated to contain higher amounts of macro-nutrients than maternal breast milk but breast milk confers important immuno-nutritional advantages for preterm or low birth weight (LBW) infants.
To determine the effect of feeding preterm or LBW infants with formula compared with maternal breast milk on growth and developmental outcomes.
We used the standard strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 9), and Ovid MEDLINE, Ovid Embase, Ovid Maternity & Infant Care Database, and CINAHL to October 2018. We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles.
Randomised or quasi-randomised controlled trials that compared feeding preterm or low birth weight infants with formula versus maternal breast milk.
Two review authors planned independently to assess trial eligibility and risk of bias, and extract data. We planned to analyse treatment effects as described in the individual trials and report risk ratios and risk differences for dichotomous data, and mean differences for continuous data, with 95% confidence intervals. We planned to use a fixed-effect model in meta-analyses and to explore potential causes of heterogeneity in subgroup analyses. We planned to use the GRADE approach to assess the certainty of evidence.
We did not identify any eligible trials.