title: Risk factors and outcomes associated with a short umbilical cord.
abstract: OBJECTIVE
  To identify risk factors and outcomes associated with a short umbilical cord.
  
  
  METHODS
  We conducted a population-based case-control study using linked Washington State birth certificate-hospital discharge data for singleton live births from 1987 to 1998 to assess the association between maternal, pregnancy, delivery, and infant characteristics and short umbilical cord. Cases (n = 3565) were infants diagnosed with a short umbilical cord. Controls (n = 14260) were randomly selected from among births without a diagnosis of short umbilical cord.
  
  
  RESULTS
  Case mothers were less likely to be overweight (body mass index 25 or more, odds ratio [OR] 0.7; 95% confidence interval [CI] 0.6, 0.8) and more likely to be primiparous (OR 1.4; 95% CI 1.3, 1.6). Case infants were more likely to be female (OR 1.3; 95% CI 1.2, 1.4), have a congenital malformation (OR 1.6; 95% CI 1.4, 1.8), and be small for their gestational age (risk ratio [RR] 1.6; 95% CI 1.4, 1.9). A short cord was associated with increased risk for maternal labor and delivery complications, including retained placenta (RR 1.6; 95% CI 1.2, 2.3) and operative vaginal delivery (RR 1.4; 95% CI 1.3, 1.5). Adverse fetal and infant outcomes in cases included fetal distress (RR 1.8; 95% CI 1.6, 2.1) and death within the first year of life among term infants (RR 2.4; 95% CI 1.2, 4.6).
  
  
  CONCLUSIONS
  Modifiable risk factors associated with the development of a short cord were not identified. Case mothers and infants are more likely to experience labor and delivery complications. Term case infants had a 2-fold increased risk of death, which suggests closer postpartum monitoring of these infants.
authors.affiliation: Department of Epidemiology, School of Public Health and Community Medicine, Molecular and Cellular Biology Program, University of Washington, Seattle, Washington 98195-7762, USA.
authors.forename: Paula
authors.initials: P
authors.lastname: Krakowiak
authors.forename: Erin N
authors.initials: EN
authors.lastname: Smith
authors.forename: Guy
authors.initials: G
authors.lastname: de Bruyn
authors.forename: Mona T
authors.initials: MT
authors.lastname: Lydon-Rochelle
mesh_terms: D000328:Adult; D001719:Birth Certificates; D016022:Case-Control Studies; D005260:Female; D005315:Fetal Diseases / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007231:Infant, Newborn; D008499:Medical Records; D007744:Obstetric Labor Complications / Q000453:epidemiology* / Q000209:etiology; D010351:Patient Discharge / Q000706:statistics & numerical data; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D012307:Risk Factors; D014470:Umbilical Cord / Q000002:abnormalities*; D014861:Washington / Q000453:epidemiology