title: Meal frequency patterns and glycemic properties of maternal diet in relation to preterm delivery: Results from a large prospective cohort study.
abstract: BACKGROUND
  Dietary habits are linked to high maternal glucose levels, associated with preterm delivery. The aim of this study was to examine the associations between meal frequency and glycemic properties of maternal diet in relation to preterm delivery.
  
  
  METHODS
  This prospective cohort study included 66,000 women from the Norwegian Mother and Child Cohort Study (MoBa). Meal frequency and food intake data were obtained from a validated food frequency questionnaire during mid-pregnancy. Principal component factor analysis was used with a data-driven approach, and three meal frequency patterns were identified: "snack meal", "main meal", and "evening meal". Pattern scores were ranked in quartiles. Glycemic index and glycemic load were estimated from table values. Intakes of carbohydrates, added sugar, and fiber were reported in grams per day and divided into quartiles. Gestational age was obtained from the Medical Birth Registry of Norway. Preterm delivery was defined as birth at <37 gestational weeks. A Cox regression model was used to assess associations with preterm delivery.
  
  
  RESULTS
  After adjustments, the "main meal" pattern was associated with a reduced risk of preterm delivery, with hazard ratios (HRs) of 0.89 (95% confidence interval (CI): 0.80, 0.98) and 0.90 (95% CI: 0.81, 0.99) for the third and fourth quartiles, respectively, and p for trend of 0.028. This was mainly attributed to the group of women with BMI ≥25 kg/m2, with HRs of 0.87 (95% CI: 0.79, 0.96) and 0.89 (95% CI: 0.80, 0.98) for the third and fourth quartiles, respectively, and p for trend of 0.010. There was no association between glycemic index, glycemic load, carbohydrates, added sugar, fiber, or the remaining meal frequency patterns and preterm delivery.
  
  
  CONCLUSIONS
  Regular consumption of main meals (breakfast, lunch, dinner) was associated with a lower risk of preterm delivery. Diet should be further studied as potential contributing factors for preterm delivery.
authors.affiliation: Department of Obstetrics and Gynecology, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Linda
authors.identifier: http://orcid.org/0000-0001-8334-2070
authors.initials: L
authors.lastname: Englund-Ögge
authors.affiliation: Department of Environmental Exposure and Epidemiology, Domain of Infection Control and Environmental Health, Oslo, Norway.|Unit for Nutrition Research, National University Hospital, Faculty of Food Science and Nutrition, University of Iceland, Reykjavik, Iceland.
authors.forename: Bryndis Eva
authors.initials: BE
authors.lastname: Birgisdottir
authors.affiliation: Department of Obstetrics and Gynecology, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Verena
authors.initials: V
authors.lastname: Sengpiel
authors.affiliation: Department of Environmental Exposure and Epidemiology, Domain of Infection Control and Environmental Health, Oslo, Norway.
authors.forename: Anne Lise
authors.initials: AL
authors.lastname: Brantsæter
authors.affiliation: Department of Environmental Exposure and Epidemiology, Domain of Infection Control and Environmental Health, Oslo, Norway.
authors.forename: Margareta
authors.initials: M
authors.lastname: Haugen
authors.affiliation: Department of Genetics and Bioinformatics, Domain of Health Data and Digitalization, Institute of Public Health, Oslo, Norway.
authors.forename: Ronny
authors.initials: R
authors.lastname: Myhre
authors.affiliation: Department of Environmental Exposure and Epidemiology, Domain of Infection Control and Environmental Health, Oslo, Norway.
authors.forename: Helle Margrete
authors.initials: HM
authors.lastname: Meltzer
authors.affiliation: Department of Genetics and Bioinformatics, Domain of Health Data and Digitalization, Institute of Public Health, Oslo, Norway.|Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden.
authors.forename: Bo
authors.initials: B
authors.lastname: Jacobsson
mesh_terms: D000328:Adult; D015331:Cohort Studies; D004032:Diet; D005247:Feeding Behavior; D005260:Female; D038321:Glycemic Index; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D039382:Maternal Nutritional Physiological Phenomena; D062407:Meals; D047928:Premature Birth / Q000453:epidemiology*; D011446:Prospective Studies