title: Can obstetric complications explain the high levels of obstetric interventions and maternity service use among older women? A retrospective analysis of routinely collected data.
abstract: OBJECTIVE
  To determine whether the higher levels of obstetric intervention and maternity service use among older women can be explained by obstetric complications.
  
  
  METHODS
  A retrospective analysis of routinely collected data from the Aberdeen Maternity and Neonatal Databank.
  
  
  METHODS
  All residents of Aberdeen city district delivering singleton infants at the Maternity Hospital 1988-1997 (28,484 deliveries).
  
  
  METHODS
  Odds ratios for each intervention in older maternal age groups compared with women aged 20-29. Interventions considered include obstetric interventions (induction of labour, augmentation, epidural use, assisted delivery, caesarean section) and raised maternity service use (more than two prenatal scans, amniocentesis, antenatal admission to hospital, admission at delivery of more than five days, infant resuscitation, and admission to the neonatal unit).
  
  
  METHODS
  Logistic regression was used to investigate the association between maternal age and the incidence of interventions. The odds ratios for each intervention were then adjusted for relevant obstetric complications and maternal socio-demographic characteristics.
  
  
  RESULTS
  Levels of amniocentesis, caesarean section, assisted delivery, induction, and augmentation (in primiparae) are all higher among older women. Maternity service use also increases significantly with age: older women are more likely to have an antenatal admission, more than two scans, a hospital stay at delivery of more than five days, and have their baby admitted to a neonatal unit. Controlling for relevant obstetric complications reveals several examples of effect modification, but does not eliminate the age effect for most interventions in most groups of women.
  
  
  CONCLUSIONS
  Higher levels of intervention among older women are not explained by the obstetric complications we considered.
authors.affiliation: Dugald Baird Centre for Research in Women's Health, Department of Obstetrics and Gynaecology, Aberdeen Maternity Hospital, UK.
authors.forename: J S
authors.initials: JS
authors.lastname: Bell
authors.forename: D M
authors.initials: DM
authors.lastname: Campbell
authors.forename: W J
authors.initials: WJ
authors.lastname: Graham
authors.forename: G C
authors.initials: GC
authors.lastname: Penney
authors.forename: M
authors.initials: M
authors.lastname: Ryan
authors.forename: M H
authors.initials: MH
authors.lastname: Hall
mesh_terms: D000328:Adult; D000367:Age Factors; D002585:Cesarean Section / Q000706:statistics & numerical data; D005260:Female; D006771:Hospitals, Maternity / Q000706:statistics & numerical data; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D016015:Logistic Models; D008423:Maternal Age; D008427:Maternal Health Services / Q000706:statistics & numerical data*; D016017:Odds Ratio; D010298:Parity; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000628:therapy*; D018566:Pregnancy, High-Risk; D012044:Regression Analysis; D012189:Retrospective Studies; D012606:Scotland / Q000453:epidemiology