title: Macronutrient composition and gestational weight gain: a systematic review.
abstract: BACKGROUND
  Abnormal gestational weight gain is associated with unfavorable pregnancy outcomes. Several risk factors have been identified, but the effect of macronutrient intake during pregnancy on gestational weight gain has not been systematically evaluated in both high-income countries and low- and middle-income countries.
  
  
  OBJECTIVE
  We conducted a systematic review of the literature in 8 different databases (until 12 August 2015) to assess whether energy intake and macronutrient intake (i.e., protein, fat, and carbohydrate) during pregnancy were associated with gestational weight gain (following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines).
  
  
  RESULTS
  Of 7623 identified references, we included 56 articles (46 observational studies and 10 trials, 28 of which were in high-income countries and 28 of which were in low- and middle-income countries). Eleven of the included articles were of high quality (20%). Results of 5 intervention and 7 high-quality observational studies suggested that higher energy intake during pregnancy is associated with higher gestational weight gain (n = 52). Results from observational studies were inconsistent for protein intake (n = 29) and carbohydrate intake (n = 18). Maternal fat intake (n = 25) might be associated with gestational weight gain as suggested by observational studies, although the direction of this association might depend on specific types of fat (e.g., saturated fat). Macronutrient intake was not consistently associated with the prevalence of inadequate or excessive gestational weight gain. Associations were comparable for high-income countries and low- and middle-income countries.
  
  
  CONCLUSIONS
  The current literature provides evidence that energy intake is associated with gestational weight gain, but the roles of individual macronutrients are inconsistent. However, there is a need for higher-quality research because the majority of these studies were of low quality.
authors.affiliation: Department of Epidemiology, m.tielemans@erasmusmc.nl.
authors.forename: Myrte J
authors.identifier: http://orcid.org/0000-0002-3133-3356
authors.initials: MJ
authors.lastname: Tielemans
authors.affiliation: Department of Epidemiology.
authors.forename: Audry H
authors.initials: AH
authors.lastname: Garcia
authors.affiliation: Department of Epidemiology.
authors.forename: André
authors.initials: A
authors.lastname: Peralta Santos
authors.affiliation: Medical Library, and.
authors.forename: Wichor M
authors.initials: WM
authors.lastname: Bramer
authors.affiliation: Department of Epidemiology.
authors.forename: Nellija
authors.initials: N
authors.lastname: Luksa
authors.affiliation: Department of Epidemiology.
authors.forename: Mateus J
authors.initials: MJ
authors.lastname: Luvizotto
authors.affiliation: Department of Epidemiology.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Moreira
authors.affiliation: Department of Epidemiology.
authors.forename: Geriolda
authors.initials: G
authors.lastname: Topi
authors.affiliation: Department of Epidemiology.
authors.forename: Ester A L
authors.initials: EA
authors.lastname: de Jonge
authors.affiliation: Department of Epidemiology.
authors.forename: Thirsa L
authors.initials: TL
authors.lastname: Visser
authors.affiliation: Department of Epidemiology.
authors.forename: Trudy
authors.initials: T
authors.lastname: Voortman
authors.affiliation: Department of Epidemiology.
authors.forename: Janine F
authors.initials: JF
authors.lastname: Felix
authors.affiliation: Departments of Obstetrics and Gynecology and.
authors.forename: Eric A P
authors.initials: EA
authors.lastname: Steegers
authors.affiliation: Department of Epidemiology, Pediatrics, Erasmus Medical Center, University Medical Center, Rotterdam, Netherlands; and Department of Global Public Health, Leiden University College the Hague, The Hague, Netherlands.
authors.forename: Jessica C
authors.initials: JC
authors.lastname: Kiefte-de Jong
authors.affiliation: Department of Epidemiology.
authors.forename: Oscar H
authors.initials: OH
authors.lastname: Franco
mesh_terms: D004032:Diet; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D039382:Maternal Nutritional Physiological Phenomena; D011247:Pregnancy; D011248:Pregnancy Complications / Q000209:etiology*; D011256:Pregnancy Outcome; D015430:Weight Gain / Q000502:physiology*
keywords: energy intake; gestational weight gain; macronutrients; pregnancy; systematic review