title: Sonographic cervical length measurement before labor induction in term nulliparous women.
abstract: OBJECTIVE
  The purpose of the study was to determine if transvaginal sonographic measurement of the cervical length is a useful method to predict successful labor induction in nulliparas.
  
  
  METHODS
  137 women who were scheduled for medically indicated induction of labor had a transvaginal sonographic measurement of the cervical length before labor induction. Inclusion criteria were: (1) singleton pregnancy; (2) gestational age between 37-42 weeks; (3) live fetus in cephalic presentation; (4) intact membranes; (5) no vaginal bleeding; (6) no previous history of uterine surgery; (7) nulliparous women, and (8) no allergy or asthma in response to prostaglandins. Induction of labor was performed within 6 h of the ultrasonographic examination, by inserting 2 mg of dinoprostone in the posterior vaginal fornix, repeated if needed every 6 h for up to three doses. When the cervix became favorable and no regular contractions were observed, amniotomy and oxytocin augmentation, starting at 1 mIU/min and increasing 1 mIU every 30 min as necessary, was performed.
  
  
  RESULTS
  All women were Caucasians and the mean age was 24.3 years (range 19-37 years). The mean cervical length was 28 mm (range 11-39 mm). The Bishop score was < or =5 in 101 women and >5 in the 36 others. Vaginal delivery occurred in 92 women (67.1%), and the vast majority of them (89 women; 96.7%) gave birth within 24 h of induction. Forty-five women (32.8%) had a cesarean section. The Bishop score was not predictive of the mode of delivery. Thirty-six of 101 women (35.6%) with a Bishop score < or =5 delivered by cesarean section, compared to 9 of 36 women with a Bishop score >5 (25%) (p = NS). Women with a cervical length <27 mm were more likely to deliver vaginally. Using this cutoff value the sensitivity of a successful labor induction was 76% and the specificity was 75.5%.
  
  
  CONCLUSIONS
  Transvaginal sonographic measurement of cervical length is a good predictor of a successful labor induction at term in nulliparas.
authors.affiliation: 1st Department of Obstetrics and Gynaecology, University of Athens, Athens, Greece. gdaskalakis@yahoo.com
authors.forename: George
authors.initials: G
authors.lastname: Daskalakis
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Thomakos
authors.forename: Leonardos
authors.initials: L
authors.lastname: Hatziioannou
authors.forename: Spyros
authors.initials: S
authors.lastname: Mesogitis
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Papantoniou
authors.forename: Aris
authors.initials: A
authors.lastname: Antsaklis
mesh_terms: D000328:Adult; D002584:Cervix Uteri / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007751:Labor, Induced; D010298:Parity; D011247:Pregnancy; D011256:Pregnancy Outcome; D016216:Ultrasonography, Prenatal