title: [Epidemiology and risk factors of preterm birth].
abstract: OBJECTIVE
  To synthesize the available evidence regarding the incidence and several risk factors of preterm birth. To describe neonatal outcomes according to gestational age and to the context of delivery.
  
  
  METHODS
  Consultation of the Medline database.
  
  
  RESULTS
  In 2010, 11% of live births (15 million babies) occurred before 37 completed weeks of gestation worldwide. About 85% of these births were moderate to late preterm babies (32-36 weeks), 10% were very preterm babies (28-31 weeks) and 5% were extremely preterm babies (<28 weeks). In France, premature birth concerns 60,000 neonates every year, 12,000 of whom are born before 32 completed weeks of gestation. Half of them are delivered after spontaneous onset of labor or preterm premature rupture of the membranes, and the other half are provider-initiated preterm births. Several maternal factors are associated with preterm birth, including sociodemographic, obstetrical, psychological, and genetic factors; paternal and environmental factors are also involved. Gestational age is highly associated with neonatal mortality and with short- and long-term morbidities. Pregnancy complications and the context of delivery also have an impact on neonatal outcomes.
  
  
  CONCLUSIONS
  Preterm birth is one of the leading cause of the under-five mortality and of neurodevelopmental impairment worldwide; it remains a major public health issue.
authors: Inserm U1153, DHU risques et grossesse, équipe de recherche en épidémiologie obstétricale, périnatale et pédiatrique, centre de recherche épidémiologie et statistique Sorbonne Paris Cité, bâtiment Port-Royal, 53, avenue de l'Observatoire, 75014 Paris, France; Université Paris Descartes, Paris, France. Electronic address: heloise.torchin@inserm.fr.
authors: H
authors: H
authors: Torchin
authors: Inserm U1153, DHU risques et grossesse, équipe de recherche en épidémiologie obstétricale, périnatale et pédiatrique, centre de recherche épidémiologie et statistique Sorbonne Paris Cité, bâtiment Port-Royal, 53, avenue de l'Observatoire, 75014 Paris, France; URC - CIC P1419, groupe hospitalier Cochin Hôtel-Dieu, Assistance publique-Hôpitaux de Paris, 75014 Paris, France; Université Paris Descartes, Paris, France.
authors: P-Y
authors: PY
authors: Ancel
mesh_terms: D005260:Female; D014943:Global Health / Q000706:statistics & numerical data*; D006801:Humans; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology* / Q000401:mortality; D012307:Risk Factors
keywords: Epidemiology; Facteurs de risque; Morbidité; Mortalité; Neonatal outcome; Premature birth; Prématurité spontanée; Risk factors; Épidémiologie