title: Rethinking placental pathology in the PSANZ classification of unexplained stillbirth at term.
abstract: BACKGROUND
  Approximately 30 per cent of stillbirths are currently classified 'unexplained' using the Perinatal Society of Australia and New Zealand (PSANZ) classification system in New Zealand. This unexplained category includes deaths with placental pathology even though the importance of placental pathology and its causal relationship to stillbirth is well described.
  
  
  OBJECTIVE
  To determine whether unexplained stillbirths in New Zealand classified using PSANZ criteria can be more usefully classified based on placental pathology.
  
  
  METHODS
  Audit of the classification of cause of death among 'unexplained antepartum death' at term by perinatal pathologist review of postmortem and/or placental pathology reports using the current PSANZ Perinatal Death Classification (PDC)10 classification and a proposed 'significant placental pathology' subclassification. The main outcome measure was a change in cause of death from unexplained term stillbirth to an alternative PSANZ classification or to significant placental pathology subcategory.
  
  
  RESULTS
  In total, 177 unexplained stillbirths with a postmortem and/or placental pathology report in New Zealand between 2007 and 2013 inclusive were reviewed. Twenty-three cases (13%) had significant placental pathology that could have been a direct cause of the stillbirth. A further seven cases (4%) were misclassified and could be better classified within another PDC category.
  
  
  CONCLUSIONS
  A classification system incorporating placental pathologies which are recognised by the current literature to be causative of stillbirth would better describe stillbirths at term in New Zealand. This would benefit parental counselling and follow-up in subsequent pregnancies. A standard approach to reporting placental pathology would benefit clinicians. Education on placental pathology for clinicians working with parents experiencing stillbirth and multidisciplinary approach to classification is also recommended.
authors.affiliation: Auckland City Hospital, Auckland, New Zealand.
authors.forename: Kate
authors.initials: K
authors.lastname: Bartlett
authors.affiliation: Auckland City Hospital, Auckland, New Zealand.
authors.forename: Jane
authors.initials: J
authors.lastname: Zuccollo
authors.affiliation: University of Auckland, Auckland, New Zealand.
authors.forename: Lynn
authors.initials: L
authors.lastname: Sadler
authors.affiliation: University of Auckland, Auckland, New Zealand.
authors.forename: Vicki
authors.initials: V
authors.lastname: Masson
mesh_terms: D002423:Cause of Death; D005260:Female; D005313:Fetal Death / Q000209:etiology*; D006801:Humans; D008485:Medical Audit; D009520:New Zealand; D010922:Placenta Diseases / Q000401:mortality; D011247:Pregnancy; D050497:Stillbirth; D047929:Term Birth
keywords: classification; pathology; placenta; stillbirth