title: Early prediction of spontaneous twin very preterm birth: a population based study 2002-2012.
abstract: OBJECTIVE
  The aim of this study was to establish early pregnancy risk indicators for spontaneous twin very preterm birth.
  
  
  METHODS
  We conducted a retrospective observational population-based study. Twenty-one potential early pregnancy risk factors were analyzed using multivariable logistic regression to determine which of them was independently associated with spontaneous twin very preterm birth.
  
  
  RESULTS
  Of 1815 spontaneous twin births 15.3% (277) occurred before 32 weeks. Previous preterm delivery (aOR 3.73; 95% CI, 2.52-5.52), nulliparity (aOR 2.94; 95% CI, 2.09-4.14), body mass index <18.5 (aOR 1.86; 95% CI, 1.12-3.10), body mass index ≥30 (aOR 1.87; 95% CI, 1.21-2.89), hysteroscopic metroplasty (aOR 1.63; 1.07-2.49), conization (aOR 2.05; 95% CI, 1.07-3.94) and monochorionicity (aOR 1.83; 95% CI, 1.28-2.63) were significantly associated with twin very preterm birth.
  
  
  CONCLUSIONS
  Pending verification in other populations, twin pregnancies at significant risk for spontaneous very preterm birth can be identified in early pregnancy using several risk indicators.
authors.affiliation: a Department of Perinatology .
authors.forename: Tanja
authors.initials: T
authors.lastname: Premru-Srsen
authors.forename: Ivan
authors.initials: I
authors.lastname: Verdenik
authors.forename: Lili
authors.initials: L
authors.lastname: Steblovnik
authors.forename: Helena
authors.initials: H
authors.lastname: Ban-Frangez
mesh_terms: D000328:Adult; D042241:Early Diagnosis; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D011247:Pregnancy; D059285:Pregnancy, Twin / Q000706:statistics & numerical data; D047928:Premature Birth / Q000175:diagnosis* / Q000453:epidemiology; D011296:Prenatal Diagnosis / Q000379:methods*; D012189:Retrospective Studies; D014427:Twins; D055815:Young Adult
keywords: Body mass index; IVF preterm delivery; high-risk pregnancy; preterm delivery; risk indicators