title: Timing of treatment initiation for mild gestational diabetes mellitus and perinatal outcomes.
abstract: OBJECTIVE
  The purpose of this study was to examine the association between gestational age (GA) at the time of treatment initiation for gestational diabetes mellitus (GDM) and maternal and perinatal outcomes.
  
  
  METHODS
  We conducted a secondary analysis of a multicenter randomized treatment trial of mild GDM in which women with mild GDM were assigned randomly to treatment vs usual care. The primary outcome of the original trial, as well as this analysis, was a composite perinatal adverse outcome that included neonatal hypoglycemia, hyperbilirubinemia, hyperinsulinemia, and perinatal death. Other outcomes that were examined included the frequency of large for GA, birthweight, neonatal intensive care unit admission, gestational hypertension/preeclampsia, and cesarean delivery. The interaction between GA at treatment initiation (stratified as 24-26, 27, 28, 29, and ≥30 weeks of gestation) and treatment group (treated vs routine care), with the outcomes of interest, was used to determine whether GA at treatment initiation was associated with outcome differences.
  
  
  RESULTS
  Of 958 women whose cases were analyzed, those who initiated treatment at an earlier GA did not gain an additional treatment benefit compared with those who initiated treatment at a later GA (probability value for interaction with the primary outcome, .44). Similarly, there was no evidence that other outcomes were improved significantly by earlier initiation of GDM treatment (large for GA, P = .76; neonatal intensive care unit admission, P = .8; cesarean delivery, P = .82). The only outcome that had a significant interaction between GA and treatment was gestational hypertension/preeclampsia (P = .04), although there was not a clear cut GA trend where this outcome improved with treatment.
  
  
  CONCLUSIONS
  Earlier initiation of treatment of mild GDM was not associated with stronger effect of treatment on perinatal outcomes.
authors.affiliation: Department of Obstetrics and Gynecology, Northwestern University, Chicago, IL. Electronic address: anna.palatnik@northwestern.edu.
authors.forename: Anna
authors.initials: A
authors.lastname: Palatnik
authors.affiliation: George Washington University Biostatistics Center, Washington, DC.
authors.forename: Lisa
authors.initials: L
authors.lastname: Mele
authors.affiliation: Department of Obstetrics and Gynecology, The Ohio State University, Columbus, OH.
authors.forename: Mark B
authors.initials: MB
authors.lastname: Landon
authors.affiliation: Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD.
authors.forename: Uma M
authors.initials: UM
authors.lastname: Reddy
authors.affiliation: Department of Obstetrics and Gynecology, The University of Texas Health Science Center at Houston-Children's Memorial Hermann Hospital, Houston, TX.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Ramin
authors.affiliation: Department of Obstetrics and Gynecology, Alpert Medical School, Brown University, Providence, RI.
authors.forename: Marshall W
authors.initials: MW
authors.lastname: Carpenter
authors.affiliation: Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, New York, NY.
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Wapner
authors.affiliation: Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Varner
authors.affiliation: Department of Obstetrics and Gynecology, University of Alabama at Birmingham School of Medicine, Birmingham, AL.
authors.forename: Dwight J
authors.initials: DJ
authors.lastname: Rouse
authors.affiliation: Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC.
authors.forename: John M
authors.initials: JM
authors.lastname: Thorp
authors.affiliation: Department of Obstetrics and Gynecology, Drexel University School of Medicine, Philadelphia, PA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Sciscione
authors.affiliation: Department of Obstetrics and Gynecology, Case Western Reserve University-MetroHealth Medical Center, Cleveland, OH.
authors.forename: Patrick
authors.initials: P
authors.lastname: Catalano
authors.affiliation: Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX.
authors.forename: George R
authors.initials: GR
authors.lastname: Saade
authors.affiliation: Department of Obstetrics and Gynecology, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Steve N
authors.initials: SN
authors.lastname: Caritis
authors.affiliation: Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Sorokin
mesh_terms: D000328:Adult; D002585:Cesarean Section / Q000706:statistics & numerical data*; D016640:Diabetes, Gestational / Q000453:epidemiology / Q000628:therapy*; D005260:Female; D005320:Fetal Macrosomia; D005865:Gestational Age; D006801:Humans; D006932:Hyperbilirubinemia / Q000453:epidemiology*; D006946:Hyperinsulinism / Q000453:epidemiology*; D046110:Hypertension, Pregnancy-Induced / Q000453:epidemiology; D007003:Hypoglycemia / Q000453:epidemiology*; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data; D054238:Perinatal Mortality; D011225:Pre-Eclampsia / Q000453:epidemiology; D011247:Pregnancy; D011256:Pregnancy Outcome; D012720:Severity of Illness Index; D013997:Time Factors; D061665:Time-to-Treatment; D055815:Young Adult
keywords: gestational age; gestational diabetes mellitus; outcome