title: A weight-gain-for-gestational-age z score chart for the assessment of maternal weight gain in pregnancy.
abstract: BACKGROUND
  To establish the unbiased relation between maternal weight gain in pregnancy and perinatal health, a classification for maternal weight gain is needed that is uncorrelated with gestational age.
  
  
  OBJECTIVE
  The goal of this study was to create a weight-gain-for-gestational-age percentile and z score chart to describe the mean, SD, and selected percentiles of maternal weight gain throughout pregnancy in a contemporary cohort of US women.
  
  
  METHODS
  The study population was drawn from normal-weight women with uncomplicated, singleton pregnancies who delivered at the Magee-Womens Hospital in Pittsburgh, PA, 1998-2008. Analyses were based on a randomly selected subset of 648 women for whom serial prenatal weight measurements were available through medical chart record abstraction (6727 weight measurements).
  
  
  RESULTS
  The pattern of maternal weight gain throughout gestation was estimated by using a random-effects regression model. The estimates were used to create a chart with the smoothed means, percentiles, and SDs of gestational weight gain for each week of pregnancy.
  
  
  CONCLUSIONS
  This chart allows researchers to express total weight gain as an age-standardized z score, which can be used in epidemiologic analyses to study the association between pregnancy weight gain and adverse or physiologic pregnancy outcomes independent of gestational age.
authors: Department of Obstetrics & Gynaecology, University of British Columbia, Vancouver, Canada. jhutcheon@cfri.ca
authors: Jennifer A
authors: JA
authors: Hutcheon
authors: Robert W
authors: RW
authors: Platt
authors: Barbara
authors: B
authors: Abrams
authors: Katherine P
authors: KP
authors: Himes
authors: Hyagriv N
authors: HN
authors: Simhan
authors: Lisa M
authors: LM
authors: Bodnar
mesh_terms: D000328:Adult; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D016014:Linear Models; D055361:Multilevel Analysis; D009765:Obesity / Q000378:metabolism; D050177:Overweight / Q000378:metabolism; D010414:Pennsylvania; D011247:Pregnancy / Q000502:physiology*; D012016:Reference Values; D012307:Risk Factors; D015430:Weight Gain; D055815:Young Adult