title: Frequency and natural history of subdural haemorrhages in babies and relation to obstetric factors.
abstract: BACKGROUND
  Subdural haematomas are thought to be uncommon in babies born at term. This view is mainly based on findings in symptomatic neonates and babies in whom subdural haemorrhages are detected fortuitously. We aimed to establish the frequency of subdural haemorrhages in asymptomatic term neonates; to study the natural history of such subdural haematomas; and to ascertain which obstetric factors, if any, are associated with presence of subdural haematoma.
  
  
  METHODS
  We did a prospective study in babies who were born in the Jessop wing of the Central Sheffield University Hospitals between March, 2001, and November, 2002. We scanned neonates with a 0.2 T magnetic resonance machine.
  
  
  RESULTS
  111 babies underwent MRI in this study. 49 were born by normal vertex delivery without instrumentation, 25 by caesarean section, four with forceps, 13 ventouse, 18 failed ventouse leading to forceps, one failed ventouse leading to caesarean section, and one failed forceps leading to caesarean section. Nine babies had subdural haemorrhages: three were normal vaginal deliveries (risk 6.1%), five were delivered by forceps after an attempted ventouse delivery (27.8%), and one had a traumatic ventouse delivery (7.7%). All babies with subdural haemorrhage were assessed clinically but no intervention was needed. All were rescanned at 4 weeks and haematomas had completely resolved.
  
  
  CONCLUSIONS
  Presence of unilateral and bilateral subdural haemorrhage is not necessarily indicative of excessive birth trauma.
authors.affiliation: Section of Academic Radiology, University of Sheffield, Sheffield, UK. e.whitby@sheffield.ac.uk
authors.forename: E H
authors.initials: EH
authors.lastname: Whitby
authors.forename: P D
authors.initials: PD
authors.lastname: Griffiths
authors.forename: S
authors.initials: S
authors.lastname: Rutter
authors.forename: M F
authors.initials: MF
authors.lastname: Smith
authors.forename: A
authors.initials: A
authors.lastname: Sprigg
authors.forename: P
authors.initials: P
authors.lastname: Ohadike
authors.forename: N P
authors.initials: NP
authors.lastname: Davies
authors.forename: A S
authors.initials: AS
authors.lastname: Rigby
authors.forename: M N
authors.initials: MN
authors.lastname: Paley
mesh_terms: D001034:Apgar Score; D001720:Birth Injuries / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D001724:Birth Weight; D002585:Cesarean Section; D036861:Delivery, Obstetric / Q000009:adverse effects; D005113:Extraction, Obstetrical; D005260:Female; D006408:Hematoma, Subdural / Q000175:diagnosis* / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007231:Infant, Newborn; D007746:Labor Presentation; D007748:Labor Stage, Second; D008279:Magnetic Resonance Imaging; D009772:Obstetrical Forceps; D011247:Pregnancy; D011446:Prospective Studies; D006113:United Kingdom / Q000453:epidemiology; D014620:Vacuum Extraction, Obstetrical