title: Does midtrimester cervical length ≥25 mm predict preterm birth in high-risk women?
abstract: OBJECTIVE
  We sought to assess pregnancy outcome along a continuum of cervical lengths (CLs) ≥25 mm.
  
  
  METHODS
  We conducted planned secondary analysis of a randomized cerclage trial of women with prior spontaneous preterm birth 17(0)-34(6/7) weeks. Outcomes of women who maintained CLs ≥25 mm were analyzed. Women with CLs <25 mm randomized to no cerclage comprised an internal comparison group.
  
  
  RESULTS
  Of 1014 screened, 153 had CL <25 mm, and 672 had CL ≥25 mm. Birth <35 weeks occurred in 16% of the ≥25 mm cohort. The relationship between CLs ≥25 mm and birth gestational age was null (P = .15). In the <25 mm group, progressively shorter CLs predicted birth <35 weeks (P < .001); this relationship was null in the ≥25 mm group (P = .17).
  
  
  CONCLUSIONS
  The continuum of CLs ≥25 mm measured between 16(0/7)-22(6/7) weeks does not predict gestational length in women with prior spontaneous preterm birth.
authors: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Alabama, Birmingham, AL, USA.
authors: John
authors: J
authors: Owen
authors: Jeff M
authors: JM
authors: Szychowski
authors: Gary
authors: G
authors: Hankins
authors: Jay D
authors: JD
authors: Iams
authors: Jeanne S
authors: JS
authors: Sheffield
authors: Annette
authors: A
authors: Perez-Delboy
authors: Vincenzo
authors: V
authors: Berghella
authors: Deborah A
authors: DA
authors: Wing
authors: Edwin R
authors: ER
authors: Guzman
mesh_terms: D000328:Adult; D023802:Cerclage, Cervical; D054791:Cervical Length Measurement; D002584:Cervix Uteri / Q000000981:diagnostic imaging; D005260:Female; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D018566:Pregnancy, High-Risk; D047928:Premature Birth / Q000175:diagnosis*; D016016:Proportional Hazards Models