title: Outcomes of Term Induction in Trial of Labor After Cesarean Delivery: Analysis of a Modern Obstetric Cohort.
abstract: OBJECTIVE
  To evaluate outcomes of induction of labor, compared with expectant management, in women attempting trial of labor after cesarean delivery (TOLAC) in a large obstetric cohort.
  
  
  METHODS
  We performed a secondary analysis of data from the Consortium on Safe Labor that included women with term (37 weeks of gestation or greater) singleton gestations and a history of one prior cesarean delivery who attempted TOLAC. Induction of labor was compared with expectant management by week of gestation from 37 to 40 weeks in both high- and low-risk cohorts. The primary outcome was failed TOLAC. Secondary outcomes included composite maternal morbidity (hysterectomy, transfusion, intensive care unit (ICU) transfer, venous thromboembolism, death), composite neonatal morbidity (5-minute Apgar score less than 5, cord pH less than 7.0, asphyxia, hypoxic ischemic encephalopathy, neonatal death), and neonatal ICU admission. Multivariate logistic regression was performed with adjustment for confounding factors.
  
  
  RESULTS
  We identified 6,033 women attempting TOLAC of whom 1,626 (27.0%) underwent induction of labor and 4,407 (73.0%) did not. Compared with expectant management, induction was associated with an increased risk of failed TOLAC at 37-39 weeks of gestation but not at 40 weeks of gestation (37 weeks of gestation, 48.5% compared with 34.3%, adjusted odds ratio [OR] 1.53, 95% confidence interval [CI] 1.02-2.28]; 38 weeks of gestation, 47.0% compared with 33.0%, adjusted OR 1.74, 95% CI 1.29-2.34; 39 weeks of gestation, 45.6% compared with 29.8%, adjusted OR 2.16, 95% CI 1.76-2.67; 40 weeks of gestation, 37.9% compared with 29.4%, adjusted OR 1.21, 95% CI 0.90-1.66). Induction was associated with an increased risk of composite maternal morbidity at 39 weeks of gestation (adjusted OR 1.87, 95% CI 1.22-2.87) and neonatal ICU admission at 37 weeks of gestation (adjusted OR 2.51, 95% CI 1.62-3.90). Induction was not associated with an increased risk of neonatal morbidity.
  
  
  CONCLUSIONS
  Induction of labor in women with one prior cesarean delivery, compared with expectant management, is associated with an increased risk of failed TOLAC. Apart from small increases in maternal morbidity at 39 weeks and neonatal ICU admission at 37 weeks of gestation, induction is not associated with an increased risk of severe maternal or neonatal morbidity.
  
  
  METHODS
  II.
authors.affiliation: Division of Maternal Fetal Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, and the Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University Hospitals Case Medical Center, Cleveland, Ohio.
authors.forename: Justin R
authors.initials: JR
authors.lastname: Lappen
authors.forename: David N
authors.initials: DN
authors.lastname: Hackney
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Bailit
mesh_terms: D000328:Adult; D002585:Cesarean Section; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology / Q000209:etiology; D007751:Labor, Induced / Q000009:adverse effects*; D016015:Logistic Models; D015999:Multivariate Analysis; D007744:Obstetric Labor Complications / Q000453:epidemiology / Q000209:etiology; D017063:Outcome Assessment, Health Care; D011247:Pregnancy; D012189:Retrospective Studies; D047929:Term Birth; D014219:Trial of Labor; D057832:Watchful Waiting