My research interests

• Sleep and Sleep Disorders

• Pediatric Diseases

• Registry Data

In my doctoral project, I researched the prevalence of sleep problems in children born extremely preterm and examined the factors during pregnancy, birth, or the neonatal period that were associated with these issues. Furthermore, I explored whether neurological impairments, behavioral problems, and lung diseases served as risk factors for sleep problems in these children. For additional information, you can find more details here: Bergen Open Research Archive: Sleep habits and sleep problems among children born extremely preterm: A Norwegian population-based cohort study (uib.no)

Academic article

• Melissa R. Balthasar; Mathieu Roelants; Bente Brannsether-Ellingsen et al. (2024). Trends in overweight and obesity in Bergen, Norway, using data from routine child healthcare 2010–2022. (external link)
• Henriette Carlsen; Torstein Vik; Guro Lillemoen Andersen et al. (2023). Cerebral palsy in children born after assisted reproductive technology in Norway: Risk, prevalence, and clinical characteristics. (external link)
• Bjørn Bjorvatn; Kristine Marie Stangenes; Nicolas Melchior Frederic Øyane et al. (2006). Subjective and objective measures of adaptation and readaptation to night work on an oil rig in the North Sea. (external link)
• Kristine Marie Stangenes; Mari Hysing; Irene Bircow Elgen et al. (2019). Sleep problems, behavioural problems and respiratory health in children born extremely preterm: a parental questionnaire study. (external link)
• Melissa Rajini Balthasar; Mathieu Roelants; Bente Brannsether-Ellingsen et al. (2023). Evaluating national guidelines for monitoring early growth using routinely collected data in Bergen, Norway. (external link)
• Kristine Marie Stangenes; Mari Hysing; Maria Vollsæter et al. (2025). Sleep problems from age two to five years and neurological outcome in children born extremely preterm: a cross-sectional study. (external link)
• Ingrid Revheim; Melissa Rajini Balthasar; Rupali Rajendra Akerkar et al. (2022). Trends in the prevalence of breastfeeding up to 6 months of age using structured data from routine child healthcare visits. (external link)
• Bjørn Bjorvatn; Kristine Marie Stangenes; Nicolas Øyane et al. (2007). Randomized placebo-controlled field study of the effects of bright light and melatonin in adaptation to night work. (external link)
• Hege Merete Aasen; Berge Solberg; Kristine Marie Stangenes et al. (2021). Trisomi 21 – insidens, diagnostikk og svangerskapsavbrud 2018. (external link)
• Kristine Marie Stangenes; Mari Hysing; Silje Katrine Elgen Fevang et al. (2018). Prenatal and neonatal factors predicting sleep problems in children born extremely preterm or with extremely low birthweight. (external link)
• Kristine Marie Stangenes; Silje Katrine Elgen Fevang; Jacob Holter Grundt et al. (2017). Children born extremely preterm had different sleeping habits at 11 years of age and more childhood sleep problems than term-born children. (external link)

Professional article

• Kristine Marie Stangenes (2019). Fødselsstatistikken 2018. (external link)
• Ferenc Macsali; Kristine Marie Stangenes; Olaug Margrete Askeland et al. (2020). Fødselsstatistikken 2019, nr 2. (external link)
• Ferenc Macsali; Kristine Marie Stangenes (2020). Fødselsstatistikken 2019. (external link)
• Kristine Marie Stangenes (2018). Fødselsstatistikken 2017, nr 2. (external link)
• Kristine Marie Stangenes (2018). Fødselsstatistikken 2017. (external link)

Media feature article

• Anne Kjersti Daltveit; Mette Løkeland-Stai; Kristine Marie Stangenes et al. (2020). Færre vert gravide. (external link)

Research report

• Mette Løkeland-Stai; Mona Tornensis Hornæs; Jon Gunnar Tufta et al. (2020). Årlig driftsrapport 2019. Helseregistre ved Folkehelseinstituttet. (external link)

Doctoral thesis (PhD)

• Kristine Marie Stangenes (2020). Sleep habits and sleep problems among children born extremely preterm: A Norwegian population-based cohort study. (external link)

Conference abstract

• Bjørn Bjorvatn; Kristine Marie Stangenes; Nicolas Melchior Frederic Øyane et al. (2006). Effects of bright light and melatonin on adaptation to night work. A randomized placebo-controlled field study at an oil rig in the North Sea. (external link)

See a complete overview of publications in Cristin.

The Impact of Early Life Events on Sleep During Childhood and in Children with Chronic Illness

Sleep is problematic for many children and adolescents, with a total of 25% experiencing one or more sleep issues during their upbringing. For some, sleep problems persist despite the existence of effective treatments for many of these issues. The healthcare system needs more knowledge about which groups of children and adolescents are at particular risk of developing sleep problems. The overarching goals of the project are:

1. Examine whether known risk factors for disrupted brain development in the prenatal, perinatal, and neonatal periods are also risk factors for sleep problems in children in the general population.
2. Investigate whether children with various types of chronic illnesses have more sleep problems than other children.
3. Explore whether adolescents born extremely preterm at the age of 18 experience sleep problems more frequently than adolescents in the control group. Investigate whether specific factors during pregnancy, birth, or the neonatal period predict these issues.

Data in the project 

Data from electronic health records (EHR) at child health clinics and the school health service (Health Profile 0-20) in Bergen Municipality are linked with data from the Medical Birth Registry. For more detailed information about this part of the project, see: Project #543143 - Forekomst og betydning av søvnvansker hos barn - Cristin. 

Data from the national follow-up study of children born extremely preterm (Project Extreme Prematurity) with data from ung@hordaland as the control group. See the description of Project Extreme Prematurity here: Prematurity | Westpaed.