Perinatal death beyond 41 weeks pregnancy: An evaluation of causes and substandard care factors as identified in perinatal audit in the Netherlands

Background: Late- and postterm pregnancy are associated with adverse perinatal outcomes, like perinatal death. We evaluated causes of death and substandard care factors (SSFs) in term and postterm perinatal death. Methods: We used data from the Perinatal Audit Registry of the Netherlands (PARS). Women with a term perinatal death registered in PARS were stratified by gestational age into early-/full-term (37.0-40.6) and late-/postterm (≥41.0 weeks) death. Cause of death and SSFs ≥41 weeks were scored and classified by the local perinatal audit teams. Results: During 2010-2012, 947/479,097 (0.21%) term deaths occurred, from which 707 cases (75%) were registered and could be used for analyses. Five hundred ninety-eight early-/full-term and 109 late-/postterm audited deaths were registered in the PARS database. Of all audited cases of perinatal death in the PARS database, 55.2% in the early-/fullterm group occurred antepartum compared to 42.2% in the late-/postterm group, while intrapartum death occurred in 7.2% in the early-/full-term group compared to 19.3% in the late-/postterm group in the audited cases from the PARS database. According to the local perinatal audit, the most relevant causes of perinatal death ≥41 weeks were antepartum asphyxia (7.3%), intrapartum asphyxia (9.2%), neonatal asphyxia (10.1%) and placental insufficiency (10.1%). In the group with perinatal death ≥41 weeks there was ≥1SSF identified in 68.8%. The most frequent SSFs concerned inadequate cardiotocography (CTG) evaluation and/or classification (10.1%), incomplete registration or documentation in medical files (4.6%) or inadequate action on decreased foetal movements (4.6%). Conclusions: In the Netherlands Perinatal Audit Registry, stillbirth occurred relatively less often antepartum and more often intrapartum in pregnancies ≥41 weeks compared to pregnancies at 37.0-40.6 weeks in the audited cases from the PARS database. Foetal, intrapartum and neonatal asphyxia were identified more frequently as cause of death in pregnancies ≥41 weeks. The most identified SSFs related to death in pregnancies ≥41 weeks concerned inadequate CTG monitoring (evaluation, classification, registration or documentation) and inadequate action on decreased foetal movements.