title: Is There a Threshold Oral Glucose Tolerance Test Value for Predicting Adverse Pregnancy Outcome?
abstract: OBJECTIVE
  This study aims to determine whether there is a threshold 3-hour oral glucose tolerance test (OGTT) value associated with accelerated risk of adverse pregnancy outcomes.
  
  
  METHODS
  In a secondary analysis of a cohort of women with untreated mild gestational glucose intolerance, we used generalized additive models with smoothing splines to explore nonlinear associations between each of the 3-hour OGTT values (fasting, 1-hour, 2-hour, and 3-hour) and adverse pregnancy outcomes, including the study's composite outcome (perinatal mortality, hypoglycemia, hyperbilirubinemia, neonatal hyperinsulinemia, and/or birth trauma), large for gestational age birth weight, small for gestational age birth weight, shoulder dystocia, neonatal hypoglycemia, gestational hypertension (gHTN), and preeclampsia.
  
  
  RESULTS
  Among the 1,360 eligible women, each timed OGTT value was linearly associated with increased odds of composite adverse outcome. We found evidence of a departure from linearity only for the association between fasting glucose and gHTN/preeclampsia, with a stronger association for values of 85 to 94 mg/dL (p = 0.03). We found no evidence of departure from linearity for any other OGTT values and measured outcomes (all chi-square test p-values ≥ 0.05).
  
  
  CONCLUSIONS
  In a population of untreated women with mild gestational glucose intolerance and fasting OGTT < 95 mg/dL, we found an increasing risk of gHTN with a fasting glucose between 85 and 94 mg/dL.
authors.affiliation: Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Stuebe
authors.affiliation: Department of Obstetrics and Gynecology, The Ohio State University, Columbus, Ohio.
authors.forename: Mark B
authors.initials: MB
authors.lastname: Landon
authors.affiliation: George Washington University Biostatistics Center, Washington, District of Columbia.
authors.forename: Yinglei
authors.initials: Y
authors.lastname: Lai
authors.affiliation: Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Mark
authors.initials: M
authors.lastname: Klebanoff
authors.affiliation: The University of Texas Health Science Center at Houston, Houston, Texas.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Ramin
authors.affiliation: Department of Obstetrics and Gynecology, Columbia University, New York, New York.
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Wapner
authors.affiliation: Department of Obstetrics and Gynecology, University of Utah, Salt Lake City, Utah.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Varner
authors.affiliation: University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Dwight J
authors.initials: DJ
authors.lastname: Rouse
authors.affiliation: Drexel University, Philadelphia, Pennsylvania.
authors.forename: Anthony
authors.initials: A
authors.lastname: Sciscione
authors.affiliation: Case Western Reserve University-MetroHealth Medical Center, Cleveland, Ohio.
authors.forename: Patrick
authors.initials: P
authors.lastname: Catalano
authors.affiliation: Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, Texas.
authors.forename: George
authors.initials: G
authors.lastname: Saade
authors.affiliation: Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Sorokin
authors.affiliation: Department of Obstetrics and Gynecology, Northwestern University, Chicago, Illinois.
authors.forename: Alan M
authors.initials: AM
authors.lastname: Peaceman
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D055815:Young Adult; D001724:Birth Weight; D015331:Cohort Studies; D004420:Dystocia / Q000453:epidemiology; D005320:Fetal Macrosomia; D005865:Gestational Age; D018149:Glucose Intolerance / Q000097:blood; D005951:Glucose Tolerance Test / Q000592:standards; D046110:Hypertension, Pregnancy-Induced / Q000453:epidemiology; D007003:Hypoglycemia / Q000453:epidemiology; D011225:Pre-Eclampsia / Q000453:epidemiology; D011256:Pregnancy Outcome; D000094422:Secondary Data Analysis