Early origins of infant lung function
Abstract
Impaired lung function in infancy is associated with an increased risk of asthma and lower lung function later in life. Fetal growth and maternal lifestyle may affect lung development. Physical activity in pregnancy is beneficial for maternal health and safe for the fetus. Fetal thoracic circumference indicates lung size, and measured in schoolchildren and adults, thoracic circumference positively predicts lung function. This thesis aimed to explore early-life factors that may be associated with infant lung function, with focus on maternal physical activity and mid-pregnancy fetal thoracic circumference, and if associations of maternal physical activity and fetal thoracic circumference with lung function differed by sex. Lung function, by tidal flow-volume loops, was measured in 899 healthy 3-month-old infants from the Preventing Atopic Dermatitis and ALLergies in Children (PreventADALL) study, a Scandinavian general population-based birth cohort study with 2394 mother-child pairs recruited at mid-pregnancy. Women physically active prior to pregnancy were most likely to stay active in the first half of pregnancy. Maternal physical activity level was not associated with birth mode nor infant size, however, infants of inactive compared to active mothers were more likely to have low lung function. Mid-pregnancy fetal thoracic circumference relative to femur length was weakly inversely associated with the ratio of time to peak tidal expiratory flow to expiratory time, and positively associated with tidal volume. Associations of maternal physical activity and fetal thoracic circumference with infant lung function did not differ by sex.List of papers
Paper I. Physical activity in pregnancy: a Norwegian-Swedish mother-child birth cohort study. Oda C. L. Carlsen, Hrefna K. Gudmundsdóttir, Karen Eline S. Bains, Randi Bertelsen, Karin C. L. Carlsen, Kai-Håkon Carlsen, Kim M. A. Endre, Berit Granum, Guttorm Haugen, Gunilla Hedlin, Christine M. Jonassen, Ina Kreyberg, Linn Landrø, Caroline-Aleksi Olsson Mägi, Björn Nordlund, Live S. Nordhagen, Kristian Pehrson, Carina M. Saunders, Katrine Sjøborg, Håvard O. Skjerven, Anne Cathrine Staff, Cecilie Svanes, Cilla Söderhäll, Riyas Vettukattil, Magdalena Værnesbranden, Johanna Wiik, Eva Maria Rehbinder. AJOG Global Reports, 2021. DOI: 10.1016/j.xagr.2020.100002. The article is included in the thesis. Also available at: https://doi.org/10.1016/j.xagr.2020.100002 |
Paper II. Infant lung function and maternal physical activity in the first half of pregnancy. Hrefna Katrín Gudmundsdóttir, Oda C. L. Carlsen, Karen Eline Stensby Bains, Martin Färdig, Guttorm Haugen, Christine M. Jonassen, Marissa LeBlanc, Björn Nordlund, Eva Maria Rehbinder, Håvard O. Skjerven, Anne Cathrine Staff, Riyas Vettukattil, Karin C. Lødrup Carlsen. ERJ Open Research, 2022. DOI: 10.1183/23120541.00172-2022. The article is included in the thesis. Also available at: https://doi.org/10.1183/23120541.00172-2022 |
Paper III. Fetal thoracic circumference in mid-pregnancy and infant lung function. Hrefna Katrín Gudmundsdóttir, Katarina Hilde, Karen Eline Stensby Bains, Martin Färdig, Guttorm Haugen, Marissa LeBlanc, Live Solveig Nordhagen, Björn Nordlund, Eva Maria Rehbinder, Håvard O. Skjerven, Anne Cathrine Staff, Riyas Vettukattil, Karin C. Lødrup Carlsen. Pediatric Pulmonology, 2023. DOI: 10.1002/ppul.26153. The article is included in the thesis. Also available at: https://doi.org/10.1002/ppul.26153 |