title: Cervical insulin-like growth factor binding protein-1 (IGFBP-1) to predict spontaneous onset of labor and induction to delivery interval in post-term pregnancy.
abstract: OBJECTIVE
  To evaluate whether insulin-like growth factor binding protein-1 (IGFBP-1) assessed in cervical secretion can predict successful induction and spontaneous onset of labor in post-term pregnancy, compared to ultrasound measurement of cervical length and Bishop score.
  
  
  METHODS
  Cohort study, originating from a randomized controlled trial.
  
  
  METHODS
  Obstetric department of a university and tertiary referral hospital, Norway.
  
  
  METHODS
  Five hundred and eight post-term women who had been randomized to induction of labor or expectant management 1 week beyond estimated day of delivery (289 [±2] days of gestation).
  
  
  METHODS
  Time to delivery was related to presence of IGFBP-1 in cervical secretion, Bishop score and ultrasound measurement of cervical length recorded at inclusion.
  
  
  METHODS
  Spontaneous onset of labor and delivery within 3 days in the expectant management, and delivery within 24 hours of induction in the induction group. Test characteristics (sensitivity, specificity and negative and positive values and likelihood ratios) for IGFBP-1, Bishop score and cervical length were calculated. Logistic regression and Cox regression were used to account for parity and body mass index.
  
  
  RESULTS
  With expectant management, IGFBP-1 predicted spontaneous labor onset and delivery within 72 hours with low sensitivity and high specificity (0.45 and 0.80, respectively), as did Bishop score (0.24, 0.92). Cervical length was more sensitive (0.67, 0.58). IGFBP-1 predicted successful induction within 24 hours with low sensitivity and high specificity (0.30, 0.85), such as Bishop score (0.06, 1.00) and cervical length (0.45, 0.76). Parity enhanced successful induction.
  
  
  CONCLUSIONS
  IGFBP-1 predicts both spontaneous labor onset and successful induction in post-term pregnancy. Bishop score and cervical length performed equally well.
authors.affiliation: Department of Gynecology and Obstetrics, Levanger Hospital, Health Trust Nord-Trøndelag, Norway. malin.doegl@helse-nordtrondelag.no
authors.forename: Malin
authors.initials: M
authors.lastname: Dögl
authors.forename: Eirik
authors.initials: E
authors.lastname: Skogvoll
authors.forename: Runa
authors.initials: R
authors.lastname: Heimstad
mesh_terms: D000328:Adult; D002584:Cervix Uteri / Q000378:metabolism* / Q000473:pathology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000378:metabolism*; D007745:Labor Onset / Q000378:metabolism*; D007751:Labor, Induced; D011237:Predictive Value of Tests; D011247:Pregnancy; D011273:Pregnancy, Prolonged / Q000175:diagnosis / Q000378:metabolism* / Q000628:therapy; D012189:Retrospective Studies; D013997:Time Factors; D016216:Ultrasonography, Prenatal; D014626:Vaginal Smears
chemical_list: D018970:Insulin-Like Growth Factor Binding Protein 1