Measuring growth consistently supports standardised newborn care

Breastfeeding supports nutrition, growth, and bonding in early life. © Ayla Meinberg / Unsplash

Growth assessment in preterm infants is an essential part of neonatal care. However, hospitals do not always measure or report growth in the same way. This variation makes it difficult to compare research findings and to understand whether nutritional care truly supports a healthy development. This commentary from researchers at the Liggins Institute, University of Auckland, discusses evidence from a systematic review and meta-analysis of protein intake in preterm infants receiving fortified human milk.

Weight gain is often used to judge whether nutrition is effective because it is easy to measure. However, the authors explain that weight gain does not necessarily reflect healthy growth. This raises an important question for standardised newborn care: are we measuring the outcomes that matter most? Consistent approaches could help ensure that growth is assessed in the same way across neonatal units.

Why growth assessment in preterm infants needs standardisation

The commentary discusses findings from a systematic review and meta-analysis that examined whether higher enteral protein intake improves growth in preterm infants receiving fortified human milk. The review found that additional protein was linked with greater weight gain. However, it showed little effect on length growth and no improvement in head circumference growth. The authors also note that studies measured both protein intake and growth in different ways, lacking standardisation. As a result, comparing findings between studies remains difficult. More consistent measurement could strengthen the evidence that guides neonatal care.

The authors argue that weight gain alone should not be treated as the main indicator of healthy growth. Instead, researchers should agree on which measures best reflect healthy development and use them consistently. They also recommend including longer term outcomes, such as neurodevelopment, whenever possible to improve understanding of nutritional care.

What this means for parents and health professionals

Clear and consistent growth measures can help parents, families and health professionals better understand how nutrition supports healthy development. Having shared standards would also make it easier to compare research findings and improve decisions about future nutritional care for preterm infants.

Parents can ask their healthcare team how their infant’s growth is being assessed and what the different measurements mean. As researchers continue to improve standardised growth assessment, families and health professionals will benefit from stronger evidence to guide care.

Paper available at: https://doi.org/10.1038/s41390-025-04270-z

Full list of authors: Bloomfield, F; Alexander, T; Cormack, B

DOI: 10.1038/s41390-025-04270-z