title: [Combined influence of preconception body mass index and gestational weight gain on fetal growth].
abstract: BACKGROUND
  The Chilean Ministry of Health has been using standards for nutritional evaluation and weight gain recommendations during pregnancy in the last 25 years. In the meantime new standards have been developed.
  
  
  OBJECTIVE
  To study the combined influence of preconception maternal nutritional status and gestational weight gain, using new standards to classify those parameters, on perinatal outcomes.
  
  
  METHODS
  A cohort of 11,465 healthy pregnant women was prospectively followed until term. Their pre-gestational nutritional status was classified using the body mass index cut-offs in use in the United States (USA). Their gestational weight gain was classified using categories proposed in a Danish study. Perinatal outcomes included were risky birth weight, i.e. < 3000 g and ≥ 4000 g, and cesarean delivery. Relative risks for those perinatal outcomes were calculated for all combined categories of pre-gestational nutritional status and gestational weight gain.
  
  
  RESULTS
  Relative risks of almost all gestational weight gain results were statistically significant for women having a normal pre-gestational nutritional status meanwhile all of them were not significant for underweight women. Overweight and obese women had similar relative risks values as normal women. However, many of them were not significant, especially in obese women.
  
  
  CONCLUSIONS
  There is an independent and combined influence of preconception nutritional status and gestational weight gain on perinatal outcomes, when using standards to classify those parameters developed in the USA and Denmark, respectively.
authors: Departamento de Salud Pública, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile. mardones@med.puc.cl
authors: Francisco
authors: F
authors: Mardones
authors: Trinidad
authors: T
authors: García-Huidobro
authors: Constanza
authors: C
authors: Ralph
authors: Marcelo
authors: M
authors: Farías
authors: Angélica
authors: A
authors: Domínguez
authors: Iván
authors: I
authors: Rojas
authors: M Teresa
authors: MT
authors: Urrutia
mesh_terms: D000328:Adult; D001724:Birth Weight / Q000502:physiology*; D015992:Body Mass Index; D002677:Chile / Q000453:epidemiology; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D016742:Preconception Care; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D012016:Reference Values; D012307:Risk Factors; D015430:Weight Gain / Q000502:physiology*