title: Cervical length at 30-32 weeks and the risk of Cesarean delivery in twin pregnancies.
abstract: OBJECTIVE
  To estimate the association between the cervical length (CL) measurement at 30-32 weeks and the mode of delivery in twin pregnancies.
  
  
  METHODS
  This was a retrospective study of a cohort, from 2005-2010, of 265 twin pregnancies with a CL measurement at 30-32 weeks. We compared the CL measurement at 30-32 weeks based on mode of delivery. We then analyzed our data across four subgroups, based on the CL measurement quartiles at 30-32 weeks. We performed this analysis in all patients, and also performed a planned subgroup analysis of 130 patients who attempted a vaginal delivery.
  
  
  RESULTS
  In all patients, including those who attempted a vaginal delivery, the mean CL at 30-32 weeks was significantly shorter in women who delivered vaginally compared with women who had a Cesarean section. The likelihood of Cesarean delivery increased significantly with increasing CL measurement across the groups defined by measurement quartiles. On adjusted analysis controlling for maternal age, race, in-vitro fertilization, chorionicity, induction of labor and prior vaginal delivery, the CL measurement at 30-32 weeks was independently associated with mode of delivery.
  
  
  CONCLUSIONS
  In twin pregnancies, the CL at 30-32 weeks is significantly associated with the likelihood of Cesarean delivery. A longer CL may represent underdevelopment of the uterus, leading to a higher risk of Cesarean delivery in labor at term.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Science, Mount Sinai School of Medicine, New York, NY, USA. nfox@mfmnyc.com
authors.forename: N S
authors.initials: NS
authors.lastname: Fox
authors.forename: A
authors.initials: A
authors.lastname: Rebarber
authors.forename: A S
authors.initials: AS
authors.lastname: Roman
authors.forename: C K
authors.initials: CK
authors.lastname: Klauser
authors.forename: D H
authors.initials: DH
authors.lastname: Saltzman
mesh_terms: D000328:Adult; D054791:Cervical Length Measurement / Q000379:methods*; D002584:Cervix Uteri / Q000000981:diagnostic imaging / Q000473:pathology*; D002585:Cesarean Section / Q000706:statistics & numerical data*; D036861:Delivery, Obstetric / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007751:Labor, Induced / Q000706:statistics & numerical data*; D008423:Maternal Age; D011237:Predictive Value of Tests; D011247:Pregnancy; D059285:Pregnancy, Twin / Q000706:statistics & numerical data; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D014481:United States