title: Prior cone biopsy: prediction of preterm birth by cervical ultrasound.
abstract: OBJECTIVE
  This study was undertaken to determine the predictive accuracy for preterm birth of transvaginal ultrasound (TVU) of the cervix in women with a prior cone biopsy.
  
  
  METHODS
  Pregnant patients with a history of cervical cone biopsy by cold knife, loop electrosurgical excision procedure (LEEP), or laser were monitored prospectively with TVU of the cervix between 16 and 24 weeks. The predictive value of TVU was evaluated by using less than 25 mm cervical length as criteria for the definition of a short cervix. The primary outcome was spontaneous preterm birth less than 35 weeks.
  
  
  RESULTS
  Of 109 women with prior cone biopsy identified, 55 had LEEP, 45 cold knife, and 9 laser cone biopsies. Thirty (28%) had a short cervix, with 9 (30%) having spontaneous preterm birth less than 35 weeks. Seventy-nine (72%) did not have a short cervix, with 5 (6%) having spontaneous preterm birth less than 35 weeks. The sensitivity, specificity, and positive and negative predictive values for spontaneous preterm birth were 64%, 78%, 30%, and 94%, respectively (relative risk [RR] 4.7, 95% CI 1.6-15.3).
  
  
  CONCLUSIONS
  TVU of the cervix is predictive of preterm birth in women with prior cone biopsy.
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Berghella
authors.forename: Leonardo
authors.initials: L
authors.lastname: Pereira
authors.forename: Aileen
authors.initials: A
authors.lastname: Gariepy
authors.forename: Giuliana
authors.initials: G
authors.lastname: Simonazzi
mesh_terms: D000328:Adult; D002584:Cervix Uteri / Q000033:anatomy & histology / Q000473:pathology; D005260:Female; D006801:Humans; D011237:Predictive Value of Tests; D011247:Pregnancy; D047928:Premature Birth / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016216:Ultrasonography, Prenatal; D014621:Vagina / Q000000981:diagnostic imaging