title: Clinical significance of early (< 20 weeks) vs. late (20-24 weeks) detection of sonographic short cervix in asymptomatic women in the mid-trimester.
abstract: OBJECTIVE
  The aim of this study was to determine whether the risk of early spontaneous preterm delivery (PTD) in asymptomatic women with a sonographic cervical length of ≤ 15 mm in the mid-trimester changes as a function of gestational age at diagnosis.
  
  
  METHODS
  This cohort study included 109 asymptomatic patients with a sonographic cervical length of ≤ 15 mm diagnosed at 14-24 weeks of gestation. Women with a multifetal gestation, cerclage and a cervical dilatation of > 2 cm were excluded. The study population was stratified by gestational age at diagnosis (< 20 weeks vs. 20-24 weeks) and by cervical length (≤ 10 mm vs. 11-15 mm). The primary outcome variables were PTD at < 28 and < 32 weeks of gestation and the diagnosis-to-delivery interval.
  
  
  RESULTS
  The median gestational age at diagnosis of a short cervix before 20 weeks and at 20-24 weeks was 18.9 and 22.7 weeks, respectively. Women diagnosed before 20 weeks had a higher rate of PTD at < 28 weeks (76.9% vs. 30.9%; P < 0.001) and at < 32 weeks (80.8% vs. 48.1%; P = 0.004), and a shorter median diagnosis-to-delivery interval (21 vs. 61.5 days, P = 0.003) than those diagnosed at 20-24 weeks. The rate of amniotic fluid sludge was higher among patients diagnosed with a short cervix at < 20 weeks of gestation than in those in whom it was diagnosed between 20 and 24 weeks (92.3% vs. 48.2%; P < 0.001).
  
  
  CONCLUSIONS
  Asymptomatic women with a sonographic cervical length of ≤ 15 mm diagnosed before 20 weeks of gestation have a dramatic and significantly higher risk of early preterm delivery than women diagnosed at 20-24 weeks. These findings can be helpful to physicians in counseling these patients, and may suggest different mechanisms of disease leading to a sonographic short cervix before or after 20 weeks of gestation.
authors.affiliation: Perinatology Research Branch, Intramural Division, NICHD/NIH/DHHS, Hutzel Women's Hospital, Bethesda, MD, USA. evaisbuch@med.wayne.edu
authors.forename: E
authors.initials: E
authors.lastname: Vaisbuch
authors.forename: R
authors.initials: R
authors.lastname: Romero
authors.forename: O
authors.initials: O
authors.lastname: Erez
authors.forename: J P
authors.initials: JP
authors.lastname: Kusanovic
authors.forename: S
authors.initials: S
authors.lastname: Mazaki-Tovi
authors.forename: F
authors.initials: F
authors.lastname: Gotsch
authors.forename: V
authors.initials: V
authors.lastname: Romero
authors.forename: C
authors.initials: C
authors.lastname: Ward
authors.forename: T
authors.initials: T
authors.lastname: Chaiworapongsa
authors.forename: P
authors.initials: P
authors.lastname: Mittal
authors.forename: Y
authors.initials: Y
authors.lastname: Sorokin
authors.forename: S S
authors.initials: SS
authors.lastname: Hassan
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000000981:diagnostic imaging / Q000502:physiology; D002584:Cervix Uteri / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D005865:Gestational Age; D006801:Humans; D007752:Obstetric Labor, Premature / Q000000981:diagnostic imaging* / Q000209:etiology; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012189:Retrospective Studies; D018570:Risk Assessment; D014463:Ultrasonography; D055815:Young Adult