Postnatal Growth Trajectories and Nutritional Strategies in Preterm Infants

Postnatal growth is one of the strongest modifiable signals of preterm infant health, shaping neurodevelopment, metabolic risk, and survival. Yet despite decades of neonatal intensive care advances, the field still lacks agreement on a fundamental question: what growth should we actually be targeting? Expert bodies endorse matching the intrauterine growth rate, but recent evidence suggests the growth velocity that truly optimizes long-term outcomes remains unknown, and that gestational age alone cannot define an appropriate goal. Compounding this, weight-based definitions of adequate growth can mislead: preterm infants frequently meet weight targets by accruing fat mass and visceral adipose tissue while remaining deficient in fat-free mass, linear growth, and head circumference. Catch-up growth measured by weight may therefore be the wrong thing to pursue.

This Research Topic aims to move the field beyond quantity-based definitions of growth toward an outcome-anchored understanding of growth quality in preterm infants. We seek to clarify which growth signals genuinely predict neurodevelopmental and metabolic outcomes, and which nutritional strategies achieve them without trading one risk for another. This matters because the trade-off is now quantified: growth faltering continues to predict poorer neurodevelopment, while accelerated early gain is linked to overweight risk peaking within the first months of corrected age and to later cardiometabolic disease.

We invite contributions addressing four interconnected objectives. First, redefining the target: interrogating whether the fetal-rate growth goal remains valid and identifying which metrics best predict outcomes across the full gestational-age spectrum, particularly in extremely preterm infants. Second, separating quantity from quality: characterizing the divergence between weight gain and fat-free, linear, and head growth, and determining when apparent catch-up reflects adiposity rather than healthy tissue accretion. Third, navigating the metabolic trade-off: defining feeding and fortification strategies that support timely catch-up without driving adverse body-composition trajectories. Fourth, closing the implementation gap: given the documented absence of consensus across nutrition guidelines, commissioning comparative-effectiveness, quality-improvement, and resource-stratified work that translates evidence into actionable protocols.

To advance these goals, we welcome submissions addressing, but not limited to, the following themes:

• Postnatal growth trajectories and the timing of catch-up growth across birth-weight and gestational-age categories
• Growth quality versus quantity: relationships among weight, linear growth, head circumference, and body composition
• Nutritional and feeding interventions, including parenteral, enteral, and fortification strategies
• Validation and comparison of body-composition and anthropometric assessment methods in preterm infants
• Regional and resource-stratified data on preterm growth patterns, including low- and middle-income settings
• Long-term growth, metabolic, and neurodevelopmental follow-up in preterm survivors
• Quality-improvement initiatives, guideline appraisal, and clinical protocols for growth monitoring in the NICU and after discharge

We welcome original research, cohort studies, systematic reviews, mini reviews, methodological studies, case reports, and perspective papers that help define not merely how fast preterm infants grow, but how well.

Article types and fees

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Case Report
• Classification
• Clinical Trial
• Editorial
• FAIR² Data
• General Commentary
• Hypothesis and Theory
• Methods
• ... View all formats

Articles that are accepted for publication by our external editors following rigorous peer review incur a publishing fee charged to Authors, institutions, or funders.

Article types

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Case Report
• Classification
• Clinical Trial
• Editorial
• FAIR² Data
• General Commentary
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• Original Research
• Perspective
• Review
• Study Protocol
• Systematic Review
• Technology and Code

Keywords: Postnatal growth, Preterm infants, Growth quality, Body composition, Neurodevelopmental outcomes, Catch-up growth, Fat-free mass, Nutritional strategies, Cardiometabolic risk, Extrauterine growth

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.