title: Maternal and neonatal outcomes among obese women with weight gain below the new Institute of Medicine recommendations.
abstract: OBJECTIVE
  To estimate whether weight loss or low gestational weight gain in class I-III obese women is associated with adverse maternal and neonatal outcomes compared with gestational weight gain within the new Institute of Medicine recommendations.
  
  
  METHODS
  This was a population-based cohort study, which included 32,991 obesity class I, 10,068 obesity class II, and 3,536 obesity class III women who were divided into four gestational weight gain categories. Women with low (0-4.9 kg) or no gestational weight gain were compared with women gaining the recommended 5-9 kg concerning obstetric and neonatal outcome after suitable adjustments.
  
  
  RESULTS
  Women in obesity class III who lost weight during pregnancy had a decreased risk of cesarean delivery (24.4%; odds ratio [OR] 0.77, 95% confidence interval [CI] 0.60-0.99), large-for-gestational-age births (11.2%, OR 0.64, 95% CI 0.46-0.90), and no significantly increased risk for pre-eclampsia, excessive bleeding during delivery, instrumental delivery, low Apgar score, or fetal distress compared with obese (class III) women gaining within the Institute of Medicine recommendations. There was an increased risk for small for gestational age, 3.7% (OR 2.34, 95% CI 1.15-4.76) among women in obesity class III losing weight, but there was no significantly increased risk of small for gestational age in the same group with low weight gain.
  
  
  CONCLUSIONS
  Obese women (class II and III) who lose weight during pregnancy seem to have a decreased or unaffected risk for cesarean delivery, large for gestational age, pre-eclampsia, excessive postpartum bleeding, instrumental delivery, low Apgar score, and fetal distress. The twofold increased risk of small for gestational age in obesity class III and weight loss (3.7%) is slightly above the overall prevalence of small-for-gestational-age births in Sweden (3.6%).
authors.affiliation: From the Division of Obstetrics and Gynecology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, University of Linköping, Linköping, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Blomberg
mesh_terms: D000293:Adolescent; D000328:Adult; D001034:Apgar Score; D002585:Cesarean Section / Q000706:statistics & numerical data; D015331:Cohort Studies; D005113:Extraction, Obstetrical / Q000706:statistics & numerical data; D005260:Female; D005320:Fetal Macrosomia / Q000209:etiology; D017408:Guidelines as Topic; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D009765:Obesity; D016017:Odds Ratio; D011225:Pre-Eclampsia / Q000209:etiology; D011247:Pregnancy; D011248:Pregnancy Complications; D011256:Pregnancy Outcome; D012042:Registries; D012306:Risk; D015430:Weight Gain; D015431:Weight Loss; D055815:Young Adult