title: A systematic approach for establishing the range of recommended weight gain in pregnancy.
abstract: BACKGROUND
  Current approaches for establishing public health guidelines on the recommended range of weight gain in pregnancy are subjective and nonsystematic.
  
  
  OBJECTIVE
  In this article, we outline how decision-making on gestational weight-gain guidelines could be aided by quantitative approaches used in noninferiority trials.
  
  
  METHODS
  We reviewed the theoretical application of noninferiority margins to pregnancy weight-gain guidelines. A worked example illustrated the selection of the recommended range of pregnancy weight gain in women who delivered at the Magee-Womens Hospital, Pittsburgh, PA, in 2003-2010 by identifying weight-gain z scores in which risk of unplanned cesarean delivery, preterm birth, small-for-gestational-age infant, and large-for-gestational-age infant were not meaningfully increased (based on noninferiority margins of 10% and 20%).
  
  
  RESULTS
  In normal-weight women, lowest risk of adverse perinatal outcome was observed at a weight-gain z score of -0.2 SDs. With a noninferiority margin of 20%, risks of adverse outcome were not meaningfully increased from the -0.2-SD reference value between z scores of -0.97 and +0.33 SDs (which corresponded to 11.3-18.4 kg). In overweight women, the recommended range was much broader: -2.11 to +0.29 SDs (4.4-18.1 kg).
  
  
  CONCLUSIONS
  The new approach illustrated in this article has a number of advantages over current methods for establishing pregnancy weight-gain guidelines because it is systematic, it is reproducible, and it provides a tool for policy makers to derive guidelines that explicitly reflect values at which risk of adverse outcome becomes meaningfully increased.
authors: From the Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada (JAH), and the Departments of Epidemiology and Obstetrics, Gynecology, and Reproductive Sciences, Graduate School of Public Health and School of Medicine, University of Pittsburgh, Pittsburgh, PA (LMB).
authors: Jennifer A
authors: JA
authors: Hutcheon
authors: From the Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada (JAH), and the Departments of Epidemiology and Obstetrics, Gynecology, and Reproductive Sciences, Graduate School of Public Health and School of Medicine, University of Pittsburgh, Pittsburgh, PA (LMB).
authors: Lisa M
authors: LM
authors: Bodnar
mesh_terms: D000328:Adult; D015992:Body Mass Index; D015331:Cohort Studies; D003661:Decision Support Techniques; D004032:Diet / Q000009:adverse effects*; D005260:Female; D006293:Health Promotion; D006786:Hospitals, Urban; D006801:Humans; D039382:Maternal Nutritional Physiological Phenomena; D018673:Nutrition Policy; D050177:Overweight / Q000503:physiopathology; D010414:Pennsylvania / Q000453:epidemiology; D017410:Practice Guidelines as Topic; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D012306:Risk; D015430:Weight Gain; D055815:Young Adult