title: Third stage of labor risks in velamentous and marginal cord insertion: a population-based study.
abstract: OBJECTIVE
  To assess whether anomalous cord insertion is associated with risk of complications in the third stage of labor.
  
  
  METHODS
  A population-based study.
  
  
  METHODS
  Norwegian Medical Birth Register.
  
  
  METHODS
  All singleton births (gestational age >16 weeks and <45 weeks) during the period 1999-2011 (n = 738,443 singletons). Deliveries by cesarean were excluded, leaving 628,680 vaginal singleton deliveries for the analyses.
  
  
  METHODS
  Calculation of odds ratios for complications in the third stage of labor (postpartum hemorrhage, manual delivery of the placenta, curettage) in velamentous and marginal cord insertion by logistic regression with adjustment for confounders.
  
  
  METHODS
  Complications in the third stage of labor, postpartum hemorrhage, manual placental removal and curettage.
  
  
  RESULTS
  Anomalous cord insertion was associated with an increased risk of complications in the third stage of labor, the risk being higher for velamentous than for marginal insertion. The risks persisted after adjusting for possible confounding factors. Velamentous cord insertion carried a 5.6% risk of a need for manual removal of the placenta, compared with the risk of 1.1% for nonvelamentous insertion (odds ratio = 5.21, 95% confidence interval 4.71-5.76) in vaginal delivery, and we found increased risks of curettage (odds ratio = 3.29, 95% confidence interval 2.87-3.77) and postpartum hemorrhage (odds ratio = 2.06, 95% confidence interval 1.77-2.39).
  
  
  CONCLUSIONS
  Marginal and especially velamentous cord insertion is associated with an increased risk of hemorrhage in the third stage of labor, need for manual removal of the placenta and curettage. Anomalous cord insertion can be identified prenatally and so possibly influence obstetric management.
authors.affiliation: Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.
authors.forename: Cathrine
authors.initials: C
authors.lastname: Ebbing
authors.affiliation: Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.|Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Torvid
authors.initials: T
authors.lastname: Kiserud
authors.affiliation: Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.
authors.forename: Synnøve L
authors.initials: SL
authors.lastname: Johnsen
authors.affiliation: Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.|Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Susanne
authors.initials: S
authors.lastname: Albrechtsen
authors.affiliation: Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.|Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Svein
authors.initials: S
authors.lastname: Rasmussen
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007749:Labor Stage, Third; D016015:Logistic Models; D009664:Norway / Q000453:epidemiology; D007744:Obstetric Labor Complications / Q000453:epidemiology*; D016017:Odds Ratio; D011247:Pregnancy; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D014470:Umbilical Cord / Q000002:abnormalities*; D055815:Young Adult
keywords: Velamentous insertion; curettage; manual removal of the placenta; marginal insertion; postpartum hemorrhage; third stage of labor