title: Is neonatal head circumference related to caesarean section for failure to progress?
abstract: BACKGROUND
  There is global concern about rising caesarean section rates. Identification of risk factors could lead to preventative measures.
  
  
  OBJECTIVE
  To describe the association between neonatal head circumference and (i) caesarean section for failure to progress, (ii) intrapartum caesarean section overall.
  
  
  METHODS
  This was a retrospective cohort study of 11 687 singleton live births with cephalic presentation, attempted vaginal birth and at least 37 completed weeks gestation from January 2005 to June 2009. Neonatal head circumference was grouped into quartiles and multiple logistic regressions performed.
  
  
  RESULTS
  The rates of caesarean section for failure to progress were 4.1, 6.4, 8.8 and 14.3% in successive head circumference quartiles. Rates of intrapartum caesarean section overall were 8.7, 12.1, 15.8 and 21.5%. The odds ratios for caesarean section for failure to progress were: 1.00, 1.33 (95% CI 1.02- 1.73), 1.54 (1.18-2.02) and 1.93 (1.44-2.57) for successive head circumference quartiles after adjusting for multiple demographic and clinical factors. The adjusted odds ratios for intrapartum caesarean section for any indication were: 1.00, 1.52 (95% CI 1.24-1.87), 1.99 (1.62-2.46) and 2.38 (1.89-3.00), respectively.
  
  
  CONCLUSIONS
  There is a strong positive relationship between head circumference quartile and both caesarean section for failure to progress and caesarean for any indication. If this finding is confirmed using ultrasound measurements, there is potential for head circumference to be incorporated into predictive models for intrapartum caesarean section with a view to offering interventions to reduce the risk of caesarean section.
authors.affiliation: RPA Women & Babies, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.|Discipline of Obstetrics, Gynaecology and Neonatology, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Bradley
authors.initials: B
authors.lastname: de Vries
authors.affiliation: Royal Brisbane & Women's Hospital, Brisbane, Queensland, Australia.
authors.forename: Bianca
authors.initials: B
authors.lastname: Bryce
authors.affiliation: University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Zandanova
authors.affiliation: RPA Women & Babies, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.
authors.forename: Jason
authors.initials: J
authors.lastname: Ting
authors.affiliation: School of Public Health, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Patrick
authors.initials: P
authors.lastname: Kelly
authors.affiliation: RPA Women & Babies, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.|Discipline of Obstetrics, Gynaecology and Neonatology, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Hala
authors.initials: H
authors.lastname: Phipps
authors.affiliation: RPA Women & Babies, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.|Discipline of Obstetrics, Gynaecology and Neonatology, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Jon A
authors.initials: JA
authors.lastname: Hyett
mesh_terms: D000328:Adult; D002585:Cesarean Section / Q000706:statistics & numerical data*; D004420:Dystocia / Q000601:surgery*; D005260:Female; D006257:Head / Q000033:anatomy & histology*; D006801:Humans; D007231:Infant, Newborn; D016015:Logistic Models; D009929:Organ Size; D011247:Pregnancy; D012189:Retrospective Studies; D012307:Risk Factors; D014219:Trial of Labor; D055815:Young Adult
keywords: caesarean section; failure to progress; head circumference; intrapartum