Positive Feeding of the Preterm Infant - a Feasibility Study of a Developmental Supportive Feeding Strategy in the NICU
Phase: NA
Conditions: Preterm Infant, Breast Feeding, Bottle Feeding, Enteral Feeding, Cue Based Feeding, Develomentally Supportive Care
Sponsor: Oslo Metropolitan University

 
 
 
Positive feeding of the preterm infant (PoP) 
A feasibility study of a developmentally supportive 
feeding strategy in the NICU 
Linn Jahren Gustavsen 
 
Main supervisor:  
Nina M Kynø 
Co-supervisors: 
Edel J Svendsen 
Bente Silnes Tandberg 
Project member: 
Claus Klingenberg 
 
NCT-number: Not yet assigned 
Uniqe protocol id: 551058 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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1. Introduction 
Infants born prematurely leave the protective environment of their mother's womb and must 
therefore develop in an extrauterine environment while their nervous system is still immature 
(Als, 1986). One central aspect affected by this is the ability to eat independently, which is a 
milestone that most infants do not achieve before reaching closer to term age (Jadcherla, 
Wang, Vijayapal, & Leuthner, 2010). Achieving full oral feeding requires medical follow-up 
from specialized healthcare services and specialized knowledge in neonatal care. Despite this, 
feeding development in premature infants is a field that relies largely on experiential 
knowledge and needs further research. This study aims to evaluate the feasibility of 
implementing a developmentally supportive feeding strategy for premature infants in a 
Neonatal Intensive Care Unit (NICU). 
 
1.1 Background 
Preterm infants (born before gestational week 37) constitute around 10% of all newborns 
worldwide and approximately 6% in Norway, according to the Norwegian Gynecological 
Association (2020) and the World Health Organization (2019). In Norway, it is a common 
practice to admit premature newborns to one of the 19 Neonatal Intensive Care Units (NICUs) 
if they are born before 35 gestational weeks. In the NICU they receive necessary medical care 
during the first days, weeks, or even months of their lives. 
Developmentally supportive care 
Developmentally supportive and neuroprotective care has evolved over 50 years and are now 
an integrated part of the treatment provided to preterm infants. This involves a range of 
interventions aimed at minimizing stress and promoting normal development for the immature 
infant (Symington & Pinelli, 2006; Westrup, 2007). In recent decades, there has also been an 
increased emphasis on including parents in the care and treatment of their infants, with NICUs 
practicing the principles of family-centered care (Gooding et al., 2011). According to The 
World Health Organization (WHO), small and sick infants have the right to receive family-
centered developmentally supportive treatment and care (World Health Organization, 2020). 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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Growth and development 
Preterm infants are low birth weight infants and in addition, many of them are born small for 
gestational age (SGA). These babies also face the risk of suboptimal weight gain during their 
stay in the NICU (Griffin, 2020; Horbar et al., 2015). Inadequate growth in premature infants 
is associated with reduced cognitive development (Guellec et al., 2016). However, a study has 
shown that breast milk can counteract these negative effects (Rozé et al., 2012). Generally, 
preterm infants have an increased risk of severe illness and early death due to cardiovascular 
disease, chronic lung disease, and diabetes in adulthood. There is though, a lack of knowledge 
about causal relationships (Risnes et al., 2021). Feeding challenges in children born 
prematurely are common and can persist into childhood, which may have negative effects on 
growth and development later in life (Britt Frisk Pados, Hill, Yamasaki, Litt, & Lee, 2021; 
Park, Thoyre, Pados, & Gregas, 2019). 
Breastfeeding and development of feeding skills 
It is well-documented that breastfeeding has health benefits for both mother and infant and 
that breast milk has positive effects for the infant (Victora et al., 2016). However, preterm 
infants are breastfed to a lesser extent than full-term infants, which can be attributed to factors 
both in the mother and the infant. (Ericson, Flacking, Hellström-Westas, & Eriksson, 2016; 
Jonsdottir, Jonsdottir, Orlygsdottir, & Flacking, 2021; Lau, 2018; Maastrup et al., 2014).). 
Most mothers of premature infants want to breastfeed, but they require closer follow-up and 
support to achieve this (Ericson & Palmér, 2019). 
The infants' feeding challenges, in addition to any medical conditions, are associated with 
immaturity due to being born prematurely. Hence, almost all infants born before 34 weeks of 
gestation require a feeding tube to ensure adequate nutrition, as medically prescribed in each 
department's nutrition protocol (Embleton et al., 2022). Most preterm infants reach full oral 
feeding by around 36 weeks of postmenstrual age (PMA). However, most of them still face 
challenges at term age, related to sleep-wake regulation, ability to maintain body tone, 
coordination of sucking and swallowing, regulation of breathing, and discomfort during 
mealtimes (Pineda, Prince, Reynolds, Grabill, & Smith, 2020).  Consequently, preterm infants 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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require closer monitoring and follow-up regarding feeding compared to full-term infants, even 
after discharge from the NICU. 
Cue-based feeding of the preterm infant 
While it is widely agreed that developmentally supportive care is best for premature infants, 
most NICUs still rely on scheduled feedings and volume-based approaches concerning 
nutrition and feeding practices in preterm infants. For the tiniest or sickest infants, careful 
control may be necessary to ensure adequate nutrition. However, for medically stable preterm 
infants who have reached around 32-34 weeks PMA and show greater behavioral maturity, 
there has been a trend in recent years to adapt to the infant's cues during the transition from 
tube feeding to full oral feeding (Lubbe, 2018). This approach, which goes by various names 
with slightly different content, involves assessing the infant's cues and behavior to determine 
readiness for oral feeding. Moreover, the definition of successful feeding is based on the 
quality of the meal rather than the quantity. 
Evidensen for å tilpasse seg barnets signaler vurderes til å være noe svak, med lav kvalitet og 
med sterk bias Enkeltstudier og kvalitetsforbedringsprosjekter tyder dog på at intervensjonen 
kan føre til at barnet bruker kortere tid i overgangen fra sonde til å spise selv og reduserer 
antall liggedøgn i sykehus, samt er medisinsk trygt. Det er ikke funnet studier som ser på 
langtidsutkomme for denne tilnærmingen, for bruk hos barn under 32 uker PMA eller at den 
er benyttet direkte opp mot sondemåltider. 
According to recent systematic reviews, the evidence supporting cue-based feeding is 
considered to have low quality and a strong bias. (McFadden et al., 2021; Watson & McGuire, 
2016). However, single studies and quality improvement projects have shown positive results 
as shortened transition time from tube feeding to oral feeding, reduced length of hospital stay, 
and that it is medically safe (Fry, Marfurt, & Wengier, 2018; Osman, 2019; Puckett, Grover, 
Holt, & Sankaran, 2008; Thomas, Goodman, Jacob, & Grabher, 2021; Ziadi, Héon, & Aita, 
2016). No studies have been found that examine long-term outcomes for this approach, its use 
in infants under 32 weeks PMA, or that it has been used related to tube feedings. 
På tross av svak evidens for selve intervensjonen, er det konsensus i fagmiljøene om at barn 
fra 32-34 uker PMA skal vurderes i forhold til sine signaler når det skal lære seg å spise selv.  

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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Despite the lack of evidence for the intervention cue-based feeding, it is generally agreed that 
infants from 32-34 weeks PMA should be assessed based on their cues when they are breast 
or bottle feeding. However, there are variations in the systematic use of this approach in 
clinical work. Healthcare professionals describe a wide use of a "trial and error" approach, 
where health personnel’s individual experience plays a role in the assessment of premature 
infants during the transition from tube feeding to full oral feeding (McFadden et al., 2021). 
Several units employ a "semi-demand-feeding" approach, which combines cue-based and 
schedule-based feeding with quantitative evaluations of meals Infants are allowed to feed 
from the breast or bottle, and then receive supplementation at the feeding tube to reach the 
medically prescribed amount (Davanzo, Strajn, Kennedy, Crocetta, & De Cunto, 2014)Infants 
are often awakened if they do not wake up on their own three to four hours after the previous 
meal. For example, for a premature infant at 35 weeks PMA, this could mean being awakened 
eight times during a day to attempt feeding, in addition to potential test weighing before and 
after breastfeeding to measure intake. This contradicts recommendations to protect sleep and 
avoid unnecessary stress, which are fundamental elements of developmentally appropriate 
care for premature infants (Altimier & Phillips, 2013). 
Both healthcare professionals and parents have described positive experiences with testing an 
intervention that considers the infant’s signals (McFadden et al., 2021). However, this 
approach is not commonly used in clinical practice in Norway, particularly not in infants 
younger than 34 weeks PMA and during tube feedings for these children. 
There is a need for a better understanding of feeding progression and challenges the preterm 
infants face. Therefore, it is important for neonatal care, to develop strategies that promote 
developmentally supportive care related to feeding and nutrition, which is an important part of 
the infants' treatment in the NICU.  
This project's objective is to develop an intervention that supports infants to reach full oral 
feeding with strategies based on the infant's cues and family-centered developmental care. 
The intervention will from now be referred to as PoP (Positive feeding of the preterm infant). 
Before implementing the intervention, it is necessary to test its feasibility. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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Testing of the intervention will be conducted as a feasibility study. A feasibility study aims to 
explore the potential for success of an intervention for subsequent implementation in a 
neonatal intensive care unit. The results will provide us with the opportunity to evaluate the 
potential for success with future implementation. Therefore, the primary outcome of this 
study is not the effect of the intervention itself but rather to assess and clarify any 
uncertainties. These uncertainties may include the organization's potential to implement the 
intervention, acceptability of the intervention, recruitment strategies, or methods of data 
collection (Orsmond & Cohn, 2015; Skivington et al., 2021). 
 
2. The aim of the study 
This study aims to develop a developmentally supportive feeding strategy and test the 
feasibility of implementing it in the NICU.  
Hypothesis: 
• A developmentally supportive feeding strategy for preterm infants (PoP) is feasible to 
implement in a modern NICU with today's available resources. 
• This strategy (PoP) ensures satisfactory growth in the infant through cue-based 
feeding. 
• Guidance in a developmentally supportive positive nutrition strategy for premature 
infants (PoP) will be perceived as useful by parents as they experience increased 
competence and confidence in feeding their infant. 
3. Design and method 
The PoP-intervention is a complex intervention and the new framework for developing and 
evaluating complex interventions from the UK Medical Research Council and the National 
Institute for Health Research will be used (Skivington et al., 2021).  
The framework describes core elements and four phases: develop or identify intervention, 
feasibility, implementation, and evaluation. This study will focus on the two first phases of 
the framework. Figure 1 provides an overview of the study and its sub-studies. 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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Figure 1. Overview of the study and its sub-studies 
STUDY PURPOSE 
To develop the PoP-intervention and test the feasibility of implementing it in the NICU 
FRAMEWORK 
Framework for developing and evaluating complex interventions from Medical Research Council guidance and National 
Institute for Health Research (Skivington, 2021) 
SUB-STUDY 1 
SUB-STUDY 2 
SUB-STUDY 3 
Develop the PoP-intervention 
Feasibility study of the PoP-
intervention 
Exploring the parents’ experiences 
with the PoP-intervention 
 
3.1 Sub-study 1 – Develop the PoP-intervention 
This sub-study falls under the phase Identify or develop intervention (Skivington et al., 2021) 
and will be carried out systematically following the process described by O’Cathain and 
colleagues (O'Cathain et al., 2019). This study is not part of the clinical trial, and will 
therefore not be elaborated further here. 
 
3.2 Sub-study 2 – Feasibility study of the PoP-intervention 
Sub-study 2 involves the feasibility phase, where there will be systematic testing of the PoP 
intervention with a perspective that goes beyond the direct effect of the intervention 
(Skivington et al., 2021). The study will be conducted in the Neonatal Intensive Care Unit, 
Vestre Viken, which is a category 3c single family-room neonatal unit. 
The study is set to begin in August 2024 and will involve premature infants born between the 
gestational age of 28 and 34 weeks, as well as infants who have been transferred from a 
regional hospital at 28 weeks postmenstrual age (PMA). To participate, parents must be able 
to speak either Norwegian or English. The inclusion period will last for one year. 
Description of the draft of the intervention that will be finalized in sub-study 1: 
The intervention protocol will be divided into three components: parent guidance, a guideline 
for monitoring the child's eating development, and a guideline for nutrition. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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1. Parent counseling: Structured counseling sessions will be conducted throughout the stay to 
provide parents with knowledge about developmentally supportive care, nutrition, and feeding 
progression in preterm infants. The program will also include a practical component on how 
parents can support their child's feeding progression and provide positive experiences during 
mealtimes. This includes when the child receives milk in their mouth during tube feeding, as 
well as when the infant is breast or bottle fed. 
 
2. Guideline for monitoring feeding progression: The progress of the infant's feeding will be 
recorded according to specific milestones. A tool called "The Milk Way" which is based on 
evidence, will be utilized to describe the path to breastfeeding (Sundhetsstyrelsen i Danmark, 
2021). In addition, the milestones related to tube feeding and progression will be documented 
and described. The parents will receive guidance on how to encourage the infant's positive 
development at each stage. The different milestones will be described in detail and the last 
one will be the ability to eat all food independently. 
3. Nutrition guideline: Nutrition guidelines specific to the study will be developed. This 
guide will be based on the current guidelines in the unit, as well as updated European 
guidelines (Embleton et al., 2022). 
The study guidelines will not deviate significantly from the unit's current guidelines but will 
allow for individual adjustments within safe boundaries. The guide will describe the minimum 
nutritional needs, vitamin supplementation, enrichment, and any limitations/possibilities for 
adjusting to the infant's cues and sleep/wake cycle. The guide will gradually provide the 
infant with increased opportunities for individual adjustment as the infant matures. The 
infant's weight will be monitored as usual according to current procedures, and the 
responsible pediatrician will prescribe the nutrition in the infant's treatment plan as is 
currently standard.  
The intervention is scheduled to be finalized in spring 2024.  

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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Data collection 
Quantitative and qualitative data will be collected from parents, healthcare personnel, 
electronic patient records, and electronic patient charts. In addition, an assessment of infant 
feeding will be collected at four weeks after term age with a validated questionnaire called 
NeoEAT assessment tool (Britt F Pados, Estrem, Thoyre, Park, & McComish, 2017).  
Analysis 
The results that will be evaluated and analyzed include criteria related to the study design, 
such as recruitment, attrition, data collection, and resource utilization, An evaluation of the 
intervention will also be conducted by examining its acceptability, adherence, and 
implementation (Skivington et al., 2021). The actual effect of the intervention will not be an 
outcome in the study, but it will instead serve as a pilot study of the intervention.  
 
3.3 Sub-study 3 - Exploring the parents’ experiences with the PoP-intervention 
As part of the phase feasibility (Skivington et al., 2021), in-depth interviews with parents 
participating in sub-study 2 will be conducted. 
The interviews aim to explore the parents' experiences with the PoP intervention and assess 
acceptability. A semi-structured interview guide will be used to ensure relevant questions are 
answered in the evaluation. The interviews will be conducted when the child is approximately 
four weeks past their due date. Informed consent for the study will be obtained as part of the 
consent for sub-study 2. The interviews will be conducted by the PhD candidate using audio 
recording. 
 
4. Project timeline 
This is a Ph.D. project being conducted by a candidate in the Health Sciences program at Oslo 
Metropolitan University. The results will be published in scientific articles and a thesis. The 
project is expected to be completed by the end of 2026. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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5. Approvals and ethical considerations 
Children are considered a vulnerable group and are specifically mentioned in the Helsinki 
Declaration, and in this study, parents will provide written consent on behalf of their children 
(World Medical Association, 2013). Therefore, the written and verbal information will clearly 
state the advantages and disadvantages of participation, as well as the voluntary nature of it. 
The project underwent an evaluation by the ethical council and was approved. The project is 
also approved by the privacy contacts at the university and health trust. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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